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top Python 5a - Random Importing Section 5 looks at additional commands that you can import and use from Python’s code libraries . A library is a collection of different commands that automatically come with Python but are separate from the main file. They can be imported (brought in) to your program by using the import command at the start of your program . Imagine Python’s library to be similar to an actual library. There are different sections in a real library (such as History, Geography, Reference) and different sections in Python’s library (such as random or time ). Each real library has many individual books in each section, just like commands in Python. randint() choice() sample() shuffle() random sleep() ctime() strftime() time from random import randint from time import ctime You can import a specific command from one of Python's libraries using the from and import commands at the top of your program . Random Numbers To generate random numbers , first import the randint command section from Python’s random code library on the first line of the program. The randint command stands for random integer . In brackets, state the number range to randomly choose from. The random value should be saved into a variable . from random import randint number = randint(1,100) print ( "A random number between 1 and 100 is" , number) = A random number between 1 and 100 is 39 = A random number between 1 and 100 is 73 = A random number between 1 and 100 is 4 The randint range does not have to be fixed values and could be replaced by variables . Below is a program where the user selects the upper and lower values of the range: from random import randint lower = int ( input ( "What is the lowest number? " )) upper = int ( input ( "What is the highest number? " )) number = randint(lower,upper) print ( "A random number between" , lower , "and" , upper , "is" , number) = What is the lowest number? 1 What is the highest number? 50 A random number between 1 and 50 is 36 = What is the lowest number? 500 What is the highest number? 1000 A random number between 500 and 1000 is 868 Random Numbers Task 1 ( Ice Comet) A special comet made of ice passes the Earth only once every one hundred years , and it hasn't been seen yet in the 21st century . Use the randint command to randomly print a year between the current year and 2099 . Example solutions: Did you know it won't be until 2032 that the ice comet will next pass Earth!? Did you know it won't be until 2075 that the ice comet will next pass Earth!? Random Numbers Task 2 ( Guess the Number) Use randint to generate a random number between 1 and 5 . Ask the user to enter a guess for the number with int and input . Print the random number and use an if statement to check if there is a match , printing an appropriate statement if there is and something different if there is not a match . Example solutions: Enter a number between 1 and 5: 4 Computer's number: 5 No match this time! Enter a number between 1 and 5: 3 Computer's number: 3 Well guessed! It's a match! Choice - Random Word Rather than just numbers, we can also randomly generate characters or strings from a specified range by using the choice command. You must first import the choice command from the random library. Choice works well with a list of values , which require square brackets and commas separating each word . Below is a program that randomly chooses from a list of animals : from random import choice animals = [ "cat" , "dog" , "horse" , "cow"] randomanimal = choice(animals) print ( "A random animal is" , randomanimal) = A random animal is cat = A random animal is horse Choice - Random Character Instead of using a list you can randomly select a character from a string . The program below randomly selects a character from the variable named 'letters ' which is the alphabet . from random import choice letters = "abcdefghijklmnopqrstuvwxyz" randomletter = choice(letters) print ( "A random letter is" , randomletter) = A random letter is e = A random letter is y Random Choice Task 1 ( Holiday Destinations ) Harriet can't decide where to go on holiday and needs help deciding. Make a list of at least 6 destinations (see the animal example above ) and use the choice command (don't forget to import it from the random library ) to print a random destination . Example solutions: Why don't you go to Paris on holiday? Why don't you go to Barcelona on holiday? Random Choice Task 2 ( Vowels ) Use the choice command to randomly select a vowel (look at the alphabet example above ). Ask the user to input a vowel and use an if statement to check if the user's letter matches the randomly selected letter . Print a suitable statement if they match and something else if they don't . Example solutions: Enter a vowel: i Random vowel: i The vowels matched! Enter a vowel: o Random vowel: u The vowels didn't match! Sample - Random Strings To choose more than one value from a set of data, use the sample command. Sample is used with a list of values and a number representing how many from that list to pick. The code sample(days,2) picks two random values from the list called days . Both examples below perform the same task but, as with most code, there is no one way to solve a problem. from random import sample days = [ "Monday" , "Tuesday" , "Wednesday" , "Thursday" , "Friday" ] two_days = sample(days , 2) print ( "You will be set homework on:" , *two_days) A separate list and then a sample . = You will be set homework on: Thursday Monday = You will be set homework on: Friday Tuesday from random import sample two_days = sample([ "Monday" , "Tuesday" , "Wednesday" , "Thursday" , "Friday" ] , 2) print ( "You will be set homework on:" , *two_days) The list and sample is combined on one line. The sample command actually makes a new list with the number of values selected (e.g. ["Tuesday" , "Thursday"] in the examples above). You can use an asterisk - * - directly before the sampled variable to print just the list values , otherwise the brackets and apostrophes will be printed too. from random import sample names = sample([ "Bob" , "Ben" , "Jen" , "Ken" ] , 2) print ( "The names are:" , names) from random import sample names = sample([ "Bob" , "Ben" , "Jen" , "Ken" ] , 2) print ( "The names are:" , *names) The names are: ['Bob', 'Jen'] The names are: Bob Jen Sample - Random Numbers You can also use the sample command to choose several integers from a given range. By implementing the range command you don’t need to individually write out each number. from random import sample numbers = sample( range (1,100) , 5) print ( "Five random numbers between 1 and 100 are:" , *numbers) Five random numbers between 1 and 100 are: 53 42 11 8 20 Five random numbers between 1 and 100 are: 74 52 51 1 6 Random Samples Task 1 ( Frost Comets) The ice comet from a previous task has broken up into four smaller frosty comets that could pass the Earth anytime from next year to the year 2095 . Print four random years in that range . Example solutions: I predict the frost comets will be seen in these years: 2093 2036 2027 2091 I predict the frost comets will be seen in these years: 2076 2033 2053 2085 Random Samples Task 2 ( Baby Boy ) Aunt Meredith is having a baby boy . Create a program that randomly selects 3 male names from a list of 10 possible names . Example solutions: Hey Aunt Meredith, how about these names: Charlie Eddie Frank Hey Aunt Meredith, how about these names: George Harold Bill ⬅ Section 4 Practice Tasks 5b - Sleep ➡

2.1: Programming Fundamentals Exam Board: OCR Specification: J277 Programming Constructs There are three constructs ( ideas of programming ) that are used to control the flow of a program : Sequence Structuring code into a logical, sequential order . Selection Decision making using if statements . Iteration Repeating code using for or while loops . Variables Variables are used to store data in programs. They can be changed as the program runs . A variable has two parts - the data value such as "Emily" and an identifier such as First_Name . An efficient program will use variables with sensible identifiers that immediately state their purpose in the program. Using variable names like 'TotalNum' and 'Profit' rather than 'num1' and 'num2' mean that other programmers will be able to work out the purpose of the code without the need for extensive comments. Local & Global Variables Large programs are often modular - split into subroutines with each subroutine having a dedicated purpose. Local variables are declared within a specific subroutine and can only be used within that subroutine . Global variables can be used at any point within the whole program . Local variable advantages Saves memory - only uses memory when that local variable is needed - global variables use memory whether they are used or not. Easier to debug local variables as they can only be changed within one subroutine. You can reuse subroutines with local variables in other programs. Global variable advantages Variables can be used anywhere in the whole program (and in multiple subroutines). Makes maintenance easier as they are only declared once. Can be used for constants - values that remain the same. Constants π As specified before, a variable is data that can change in value as a program is being run. A constant is data that does not change in value as the program is run - it is fixed and remains the same. An example of a constant in maths programs is pi - it will constantly remain at 3.14159 and never change. Operators Comparison Operators Comparison operators are used to compare two data values . A table of common comparison operators used in programs are below: Arithmetic Operators Arithmetic operators are used to mathematically manipulate values . The most common arithmetic operators are add (+ ), subtract (- ), multiply (* ) and divide (/ ). Further arithmetic operators are shown below: Modulo division (also known as modulus ) reveals the remainder from the last whole number . For example: 9 % 4 = 1 (4 goes into 9 twice (8) with a remainder of 1) Integer division (also known as quotient ) reveals the ‘whole number of times ’ a number can be divided into another number : 9 // 4 = 2 (4 goes into 9 fully, twice) The symbol ^ represents exponentiation . However, Python uses ** to represent exponentiation. For example '2^3 = 8' is equivalent to '2³ = 8'. Logical Operators Logical operators typically use TRUE and FALSE values which is known as Boolean . You can find more information about Boolean values in section 4.1 . Q uesto's Q uestions 2.1 - Programming Fundamentals: Programming Constructs 1. Describe and draw a diagram for the 3 programming constructs . [6 ] Variables 1. What is the difference between local and global variables ? [4 ] 2. Describe two advantages of using local variables . [2 ] 3. Describe two advantages of using global variables . [2 ] 4. What is a constant ? Give an example . [2 ] 1.3 - Searching & Sorting Theory Topics 2.2 - Data Types

8.2: Understanding Algorithms Exam Board: Eduqas / WJEC Specification: 2020 + What is an algorithm? An algorithm is a set of instructions , presented in a logical sequence . In an exam you may be asked to read and understand an algorithm that has been written. To prove your understanding you may be asked to respond by actions such as listing the outputs of the algorithm, correcting errors or identifying an error within it. Programmers create algorithm designs as a method of planning a program before writing any code. This helps them to consider the potential problems of the program and makes it easier to start creating source code. There are two main methods of defining algorithms : Defining Algorithms - Pseudocode & Flowcharts Pseudocode Pseudocode is not a specific programming language but a more general method of describing instructions . It should be unambiguous, and it should not resemble any particular kind of programming language (e.g. Python or Java), so it can theoretically be turned into working code in any language. Generally, pseudocode can be written in any way that is readable and clearly shows its purpose. However, the Eduqas exam board advises that pseudocode for the programming exam should follow the conventions below : Annotation { Write your comment in curly brackets} Define data type price is integer firstname is string Declare a variable's value set price = 100 set firstname = "Marcella" Input / output output "Please enter your first name" input firstname Selection (must have indentation) if firstname = "Steven" then output "Hello" + firstname elif firstname = "Steve" then output "Please use full name" else output "Who are you?" end if Iteration (while loop) while firstname ! = "Steven" output "Guess my name." input firstname repeat Iteration (for loop) for i in range 10 input item next i Define a subroutine Declare Sub1 [Subroutine content indented] End Sub1 Call a subroutine call Sub1 Flowcharts A flowchart can be used to visually represent an algorithm. The flowchart symbols are: Algorithm Examples Below are two different methods for representing the same algorithm - a program to encourage people to buy items cheaply at a supermarket. The program allows the price of items in a supermarket to be entered until the total reaches 100. The total price and the number of items entered are tracked as the program loops. Once the total reaches 100 or more, an if statement checks how many items have been entered and a different message is printed if there are 20 or more items, 30 or more items or less than 20 items. Pseudocode Flowchart {This is a program to see how many items you can buy in a supermarket before you spend over £100} total is integer, itemsentered is integer, itemprice is integer set total = 0 set itemsentered = 0 while total < 100 output "enter the price of the next item" input itemprice total = total + itemprice itemsentered = itemsentered + 1 repeat if itemsentered >= 20 then output "You are on your way to saving money." elif itemsentered => 30 then output "You're a real money saver." else output "Look for better deals next time." end if Reading Algorithms In an exam you may be asked to read an algorithm and prove your understanding , most commonly by listing the outputs . Start from the first line and follow the program line by line , recording the value of variables as you go . When you encounter a for loop , repeat the indented code as many times as stated in the range . Example Algorithm: Start NewProgram i is integer maxvalue is integer input maxvalue for i = 1 to maxvalue output (i * i) ??????? output 'program finished' End NewProgram Example Questions: 1. List the outputs produced by the algorithm if the 'maxvalue' input is 5 . 2. State the code that has been replaced by '???????' and what the code's purpose is. Example Answers: 1. Outputs: 1 4 9 16 25 program finished 2. Missing Code: next i Purpose: Moves the loop to the next iteration. Watch on YouTube Q uesto's Q uestions 8.2 - Understanding Algorithms: 1a. Read the algorithm shown on the left and list all outputs in the correct order if the inputs are 2 for height and 72 for weight . 1b. Give the code that is missing from line 25 . 8.1 - Programming Principles Theory Topics 8.3 - Writing Algorithms

1.2: Designing Algorithms Exam Board: OCR Specification: J277 What is an algorithm? An algorithm is a set of instructions , presented in a logical sequence . In an exam you may be asked to read and understand an algorithm that has been written. To prove your understanding you may be asked to respond by actions such as listing the outputs of the algorithm, correcting errors or identifying an error within it. Programmers create algorithm designs as a method of planning a program before writing any code. This helps them to consider the potential problems of the program and makes it easier to start creating source code. There are two main methods of defining algorithms are pseudocode and flowcharts . In exams , OCR will display algorithms in their own 'OCR Exam Reference Language '. Visit the Python section of CSNewbs ---> OCR Exam Reference Language T he OCR exams require specific questions to be written either in OCR Exam Reference Language (shown below) or a high-level programming language such as Python . Basic Commands Annotation // Comments are written using two slashes Assignment name = "Harold" age = 49 Constants and Global Variables constant tax = 15 global name = "Admin" Input / Output name = input ( "Enter your name") print ("Transaction Complete") Casting str (29) int ("102") float (30) bool ("False") Random Number number = random (1,100) Selection Selection (if - then - else) if firstname == "Steven" then print("Hello" + firstname) elif firstname == "Steve" then print("Please use full name") else print("Who are you?") end if Selection (case select) switch day: case “Sat”: print(“It is Saturday”) case “Sun”: print(“It is Sunday”) default : print(“It is a Weekday”) endswitch Iteration Iteration (for loop) for i = 1 to 10 step 1 input item next i Iteration (while loop) while firstname ! = "Steven" firstname = input("Try again:") endwhile Iteration (do while loop) do firstname = input("Guess name:") until firstname == "Steven" String Handling Length of a String word = "dictionary" print(word.length ) outputs 10 Substrings word = "dinosaurs" print(word.substring (2,3)) outputs nos print(word.left (3)) outputs din print(word.right (4)) outputs aurs Concatenation name = "Penelope" surname = "Sunflower" print(name + surname) String Cases phrase = "The Cat Sat On The Mat" print(phrase .lower ) print(phrase .upper ) ASCII Conversion ASC ("C") returns 67 CHR (100) r eturns "d" File Handling File Handling - Reading Lines file1 = open ("Customers.txt") while NOT file1.endOfFile() print(file1.readLine() ) endwhile file1.close() File Handling - Writing to a (New) File newFile ("paint.txt") file2 = open ("paint.txt") paint = input("Enter a paint colour:") file.writeLine (paint) file2.close() Arrays Declare Array array names[3] array names = "Ella", "Sam", "Ali" Declare 2D Array array grid[4,5] Assign Values names[2] = "Samantha" grid[1,3] = "X" More Programming Keywords Connecting strings together using the + symbol is called concatenation . Extracting certain parts of a string (e.g. using .substring() ) is called slicing . An if statement within an if statement or a loop within a loop is called nesting . Flowcharts A flowchart can be used to visually represent an algorithm. It is more likely you will need to be able to interpret a flowchart rather than draw one. The flowchart symbols are: The terminator symbol is also known as a terminal . Algorithm Examples Below are two different methods for representing the same algorithm - a program to encourage people to buy items cheaply at a supermarket. The program allows the price of items in a supermarket to be entered until the total reaches 100. The total price and the number of items entered are tracked as the program loops. Once the total reaches 100 or more, an if statement checks how many items have been entered and a different message is printed if there are 20 or more items, 30 or more items or less than 20 items. Pseudocode // This is a program to see how many items you can buy in a supermarket before you spend over £100} total = 0 itemsentered = 0 while total < 100 itemprice = input ("enter the price of the next item") total = total + itemprice itemsentered = itemsentered + 1 endwhile if itemsentered >= 20 then print ("You are on your way to saving money.") elif itemsentered => 30 then print ("You're a real money saver.") else print ("Look for better deals next time.") endif Flowchart Reading Algorithms In an exam you may be asked to read an algorithm and prove your understanding , most commonly by listing the outputs . Start from the first line and follow the program line by line , recording the value of variables as you go . When you encounter a for loop , repeat the indented code as many times as stated in the range . Example Algorithm: procedure NewProgram() maxvalue = input() for i = 1 to maxvalue output (i * i) ??????? print("program finished") endprocedure Example Questions: 1. List the outputs produced by the algorithm if the 'maxvalue' input is 5 . 2. State the code that has been replaced by '???????' and what the code's purpose is. Example Answers: 1. Outputs: 1 4 9 16 25 program finished 2. Missing Code: next i Purpose: Moves the loop to the next iteration. Watch on YouTube Structure Diagrams Structure diagrams display the organisation (structure ) of a problem in a visual format , showing the subsections to a problem and how they link to other subsections . The noughts and crosses structure diagram below has subsections in light yellow. Each subsection could be coded by a different person . Structure diagrams are different to flowcharts (those show how data is input, processed and output within a program or system). You may be asked in an exam to draw or fill in a simple structure diagram . Trace Tables Trace tables are used to track the value of variables as a program is run . They can be used to manually track the values in order to investigate why the program isn't working as intended . Each row in the trace table represents another iteration . Each column stores the value of a variable as it changes. See below how the trace table is updated for the simple algorithm on the left. num1 = 2 num2 = 5 for i = 1 to 3 output (num1 + num2) num2 = num2 - 1 next i print("complete") For most algorithms, not every variable will be updated in each iteration . Values may not be entered in the order of the trace table either. For example, each iteration outputs num1 + num2 and then decreases the value of num2 by 1. Q uesto's Q uestions 1.2 - Designing Algorithms: 1. What is the definition of an algorithm ? Name two ways an algorithm can be designed . [ 3 ] 2. Using a high-level programming language such as Python , or the OCR Exam Reference Language , write an algorithm that inputs 6 decimal numbers and outputs the total , largest , smallest and average values. [ 8 ] For example, entering 3.1 , 5.3 , 2.3 , 5.4 , 2.9 and 4.4 would output 23.3 (total), 5.4 (largest), 2.3 (smallest) and 3.9 (average). 3. Draw and label the flowchart symbols . [ 6 ] 4. What is the purpose of a structure diagram ? [ 2 ] 5. Create a trace table for the NewProgram() algorithm in the Reading Algorithms section on this page. [ 7 ] 1.1 - Computational Thinking Theory Topics 1.3 - Searching & Sorting

top Python 6a - For Loops Types of Loop The third construct of programming (after Sequence and Selection) is Iteration . If you iterate something, then you repeat it. There are two key loops to use in Python: for loops and while loops . A for loop is count controlled – e.g. “For 10 seconds I will jump up and down”. The loop will continue until the count (e.g. 10 seconds) has finished . A while loop is condition controlled – e.g. “While I am not out of breath, I will jump up and down.” The loop will continue as long as the condition remains true . Simple For Loops (1 Range Value) for i in range (5): print ( "This is a loop!" ) This is a loop! This is a loop! This is a loop! This is a loop! This is a loop! for i in range (8): print ( "Jaffa Cakes aren't biscuits" ) Jaffa Cakes aren't biscuits Jaffa Cakes aren't biscuits Jaffa Cakes aren't biscuits Jaffa Cakes aren't biscuits Jaffa Cakes aren't biscuits Jaffa Cakes aren't biscuits Jaffa Cakes aren't biscuits Jaffa Cakes aren't biscuits The i is a count variable , it is used to measure each iteration (turn) of the loop. In the range brackets write the number of times to loop the indented code. Don’t forget the colon at the end and remember that everything you want to repeat must be indented (press tab key once). For Loops Task 1 (Repeat Your Name ) Example solutions (shortened): Create a simple for loop that prints your name twenty times. For Loops Task 2 (Are We There Yet? ) Christopher Christopher Christopher ... Create a simple for loop that prints the sentence 'Are we there yet?' 150 times. Are we there yet? Are we there yet? Are we there yet? ... Counting Using i (2 Range Values) For loops can be used to count by referring to the iteration inside the loop itself using i : for i in range (5): print ( "Loop number" , i) Loop number 0 Loop number 1 Loop number 2 Loop number 3 Loop number 4 for i in range (1,6): print ( "Loop number" , i) Loop number 1 Loop number 2 Loop number 3 Loop number 4 Loop number 5 There are two important things to know about how Python counts using for loops. Python will automatically start counting at 0 rather than 1. The second value in the range is an exclusive limit - it will stop 1 before this value. For example, if you wanted to count 1 to 10 you would need to write range(1,11) . For Loops Task 3 (100 to 150 ) Create a for loop that prints all numbers from 100 to 150 . You don't need to print any additional text, just the i variable. Example solution (shortened): 100 101 102 ... ... 148 149 150 Using a Step (3 Range Values) A third value can be added to the range brackets of a for loop to define a step . A step is the number to go up (or down ) with each iteration . for i in range (2,11,2): print ( i) 2 4 6 8 10 for i in range (18,0,-3): print ( i) 18 15 12 9 6 3 In most programs defining a step is not essential , Python will assume it is +1 if you don't include it. For Loops Task 4 (Even Numbers 10 to 30 ) Example solution for Task 4 (shortened): Create a for loop that prints all even numbers from 10 to 30 . Use a step . For Loops Task 5 (Countdown ) Use a for loop with a negative step to print a countdown from 10 to 1 . 10 12 14 ... ... 26 28 30 Using Variables with For Loops Variables can be used to make for loops suitable for a range of different purposes. loopnum = int ( input ( "Times to repeat: " )) for i in range (loopnum): print ( "Hello!" ) Times to repeat: 4 Hello! Hello! Hello! Hello! The loop above uses a variable in the range brackets to repeat the loop the specific number of times that the user enters . loopnum = int ( input ( "Times to repeat: " )) word = input ( "Word to repeat: " ) for i in range (loopnum): print (word ) Times to repeat: 3 Word to repeat: velociraptor velociraptor velociraptor velociraptor The loop above uses two variables that are input by the user ; one to define the range and another that is printed . For Loops Task 6 (Many Happy Birthdays ) Example solution for Task 6 (shortened): Ask the user to input their age then print 'Happy Birthday! ' that many times. For Loops Task 7 (House Number and Name ) Ask the user to enter their house number (e.g. 15 if they lived at 15 Cherry Road) and their name . Print their name as many times as their house number . For example, if Hannah lived at 103 Apple Lane then Hannah would be printed 103 times . Enter your age: 5 Happy Birthday! Happy Birthday! Happy Birthday! Happy Birthday! Happy Birthday! ⬅ Section 5 Practice Task s 6 b - While Loops ➡

3.5 - Business Systems Exam Board: OCR Specification: 2016 - Unit 1 A business may use several types of complex systems to manage data , communicate with customers and ensure efficient business practice . Management Information System (MIS) A management information system (MIS ) is used to collect , store , analyse and present data for an organisation. The system processes a large amount of data and organises it (such as in databases) so that it can be used for decision-making and general data analysis . An efficient MIS can be used to display the financial status of an organisation, highlight areas of improvement and generate sales forecasts based on current data. Specifically, a bank could use an MIS for: Looking at the number of customers that visit each branch . Forecasting potential profits based on historical data of previous years. Profiling customers based on their actions and behaviour . Identifying specific customers with low activity to target them for email campaigns . Benefits of an MIS: Integrated system: A Management Information System shares a large amount of data from multiple departments within an organisation to produce accurate reports. For example, financial data can be used to generate accurate pay slips. Decision Making: An MIS can be used to inform an organisation's decision making by highlighting areas that need improvement within the company. Powerful analysis: An MIS will use large data sets to provide accurate data analysis that can be used in many different ways by an organisation. Trends and patterns can be identified easily. Backup capabilities: Data can be stored centrally and backed up easily if a disaster occurs. Limitations of an MIS: Cost and installation: An MIS is an expensive tool that needs to be professionally set up and requires technical knowledge to maintain. Requires accurate data: If any data is incorrect or out of date then the analysis will consequently be inaccurate . Potentially disastrous decisions could be made as a result of incorrect data. Training: Employees will need to be trained to use the software accurately for maximum efficiency. Customer Relationship Management (CRM) A CRM system is used to improve the relationship between an organisation and its customers . It can be used to increase customer loyalty with those who already subscribe to their services as well as used to try and increase the customer base by attracting new customers. The ultimate goal of a CRM system is to increase and retain customers which will result in more sales and higher profits . Examples of CRM systems: Marketing teams tracking which promotions customers are responding well to . Customer service teams responding quickly to customer complaints , through a variety of channels (such as social media, emails and telephone calls). Marketing teams rewarding customers who have spent a certain amount in a year. Standard Operating Procedures (SOP) A standard operating procedure is a comprehensive step-by-step guide of how to carry out a business routine. An organisation will create an SOP to abide by legal requirements and high company standards . SOPs must be followed in exactly the same method each time and by each employee to ensure the same outcome and remove any inconsistencies . Benefits of Standard Operating Procedures: Ensures consistency: The outcome should be the same each time when following SOPs which ensures an efficient result . Fewer errors: If all employees follow the SOP carefully then there should be no errors . Meets legal requirements : The SOPs will be designed to meet up-to-date legislation as well as any standards that the company have set. Limitations of Standard Operating Procedures: Inflexible practice: A lot of time may be spent on creating the paperwork and admin instead of the actual job. Legal updates: The SOPs must be periodically reviewed and updated to take into account any new laws . Sales Ordering Process (SOP) This is the process of a customer buying a product or service and the company reviewing the purchase . A sales order process ( SOP ) is important as it creates a clear plan for ordering a product . Each department can use the sales order to know exactly what jobs to perform. Help Desk Help desk software is used to provide real-time support to a user from a trained member of staff to overcome a technical problem . The customer logs an issue in the form of a ticket and is assigned a technician . As the technician tries to communicate with the user and solve the issue they must follow a service level agreement that defines the high standards the technician must keep to. When the problem has been solved the ticket is closed . All tickets are archived so that persistent problems can be checked to see what worked previously . If Help Desk software is used within a company by employees (rather than with external customers) to report and solve issues, it is known as ' in-house ' . Benefits of Help Desk software: Keeping Track: C ustomers can see that their issues are being dealt with and administrators have clear records of the problem. Audit Logs: All tickets are archived so if a problem occurs on the same machine the previous solution can be attempted again . Communication : Formal messages between the customer and the administrator mean there are no mixed messages and a running dialogue can take place as the problem is fixed. Limitations of Help Desk software: Cost : Setting up the necessary software and hardware and paying for an administrator to run the system can cost a large amount of money. Availability issues: A technician might not be available 24/7 or during holidays. Formal structure: This is a formal system that takes time to record and respond to which might annoy staff when it is only a minor issue to be fixed, like resetting a password. Knowledge: Technicians need technical expertise regarding the company's computer systems and need to be able to fix both hardware and software issues. This might require additional training every few years. Ticket Response Time: Administrators must ensure that all tickets are read and responded to in reasonable time so that productivity in the company is not affected. Q uesto's Q uestions 3.5 - Business Systems: 1a. What is the purpose of an MIS ? [ 2 ] 1b. Describe 3 ways a bank could use an MIS . [ 3 ] 1c. Describe the benefits and limitations of an MIS . [10 ] 2a. What is the purpose of a CRM ? [ 4 ] 2b. Describe 3 ways that a CRM could be used by a company . [6 ] 3a. What are standard operating procedures (SOP ) and why are they used? [ 4 ] 3b. Describe the benefits and limitations of SOPs . [ 10 ] 4a. What is the sales ordering process ( SOP )? [ 2 ] 4b. Why is the SOP important in a company? [ 2 ] 4c. Summarise the 3 stages of the SOP . [ 4 ] 5a. What is the purpose of help desk software? [ 2 ] 5b. Explain how help desk works , including tickets , technicians and service level agreements . [3 ] 5c. Describe the benefits and limitations of Help Desks . [ 10 ] A typical sales order process will work as follows: 1. The customer orders a product or service, usually via an email or telephone conversation . 2. The order is confirmed and a sales order is created. This is a document that lists the customer’s requirements and exactly what they have purchased . 3. The sales order is sent to the relevant departments (e.g. production , finance and delivery ) so they can fulfil the customer’s request . Once the order has been completed, the customer will be sent an invoice for payment . 3.4 - Connection Methods Topic List 4.1 - Communication Methods

2.2: Applications Software Exam Board: OCR Specification: 2016 - Unit 1 What is applications software? Don't confuse applications software and apps . Apps generally have a single purpose , such as a game like Angry Birds or the torch tool on a phone. Applications software can be used for a number of different functions depending on the user's needs and their purpose. Productivity Software This is general use software for completing a range of tasks accurately and efficiently . Key examples include word processors (e.g. Microsoft Word or Google Docs), presentation software (e.g. Microsoft PowerPoint or Google Slides) and web browsers (e.g. Microsoft Edge or Google Chrome). Email applications (e.g. Microsoft Outlook or Gmail) are beneficial to organisations because staff can send information to many customers at once which is a simpler and less costly method of communication than something like sending letters or leaflets in the mail. Emails can also include attachments of important documents and include multimedia elements like images and videos to make communication more interesting . Databases and Spreadsheets Database tables and spreadsheets can store both numerical and textual data ready for analysis . Examples include simple database tables and financial spreadsheets of a company's profits each year. Microsoft Access is an example of database software that uses tables of records and Microsoft Excel is an example of spreadsheet software . Data can be sorted numerically or alphabetically for both software types but graphs can be created from spreadsheets to visualise data . When using spreadsheets (or databases) records can be locked ('record locking' ) so that only one person can make edits to a specific record at any one time. Edits will be saved before unlocking the file. This will stop data being incorrectly overwritten and will ensure that the data in the spreadsheet is up-to-date, accurate and fit for purpose. Development Tools These are tools for programmers who are creating or modifying software . An integrated development environment ( IDE ) is software used to create , edit and debug (fix) programs . An IDE features a number of tools , including: A source code editor to type program code into. It may contain features such as error highlighting and automatic formatting . Because IDEs use high-level languages like Python or Java , a translator is required to convert the source code into machine code ( binary ) so that it can be understood and processed by the CPU . A compiler is a type of translator that converts instructions into machine code (binary) in one go . An interpreter is a type of translator that converts instructions into machine code (binary) line by line . A debugger is used to test code and display errors . Other development tools aid programmers with developing and maintaining websites and apps for phones / tablets. An advantage of databases over spreadsheets is that data can be atomised - meaning it can be stored in separate tables (e.g. one for patients and one for doctors ) with records linked through relationships . This minimises data redundancy (duplication ), meaning there is a lower chance of making errors , and it is easier to search through the table as each record will only appear once . A search through a database is called a 'query '. Business Software This is specialist software for businesses , often made bespoke for an organisation based on their needs . Types of business software: Project management software allows teams of workers to collaborate and split large projects into manageable tasks with clear deadlines and assigned roles . A management information system (MIS ) processes a large amount of data and organises it for use in decision-making and general data analysis . See more about an MIS in section 3.5 . Multimedia programs such as video editors or animation suites can be used to create high-quality videos with images , audio and video clips . Collaboration tools for businesses allow employees to share ideas and resources in real-time . Publishing software allows users to implement text and images into eye-catching designs such as posters , leaflets or static adverts to include on a website. Expert systems use large databases for automatic decision-making , often making use of AI to quickly solve complex problems . A healthcare example of an expert system is a medical diagnosis program that may suggest possible illnesses when a patient's symptoms are input . CAD / CAM One example of business software used for the design and manufacture of a product is CAD / CAM (C omputer-A ided D esign / C omputer-A ided M anufacturing). CAD is used to create highly detailed digital designs and CAM translates these designs into instructions for manufacturing machines to make the product physically. These software packages use 3D modelling and image rendering along with exact measurements to create precise designs ready to be manufactured . Engineers use them to design and make mechanical parts and architects use them to create detailed building models and blueprints . Q uesto's Q uestions 2.2 - Applications Software: 1. State four different kinds of productivity software and briefly describe how each could be used . For example: "Word processors can be used to type up a letter in an office or write an essay for school." [8 ] 2. Describe two differences between database and spreadsheet software. [2 ] 3a. What is an Integrated Development Environment ? [1 ] 3b. Describe three tools used in an IDE. [6 ] 4. Giving brief examples of how they can be used, state four different types of business software . [8 ] 5. Suggest how a website design company could use each of the three types of applications software (Productivity Software , Development Tools and Business Software ). [ 6 ] 2.1 - Types of Software Topic List 2.3 - Utility Software

1.7 - Units of Measurement Exam Board: OCR Specification: 2016 - Unit 1 All computer systems communicate , process and store data using binary because this is the format that the processor understands . Binary is a number system consisting entirely of 0s and 1s . A single binary data value (a 0 or a 1 ) is called a bit . 4 bits is called a nibble (e.g. 0101 or 1100). 8 bits is called a byte (e.g. 10101001 or 01011100). There are two main measurement systems : Metric Units of Measurement The gap between units when using metric values (also known as the decimal system ) is always 1,000 . For example, there are 1,000 bytes in 1 kilobyte and 1,000 kilobytes in 1 megabyte . To convert between metric units , divide by 1,000 when moving to a larger unit (e.g. 500 megabytes is 0.5 gigabytes ) and multiply by 1,000 when moving to a smaller unit (e.g. 4.7 terabytes is 4,700 gigabytes ). For example, 8,520 KB is the same as 8.52 MB or 0.00825 GB . Metric values (usually) have a prefix ending in ‘ a ’ such as mega byte or giga byte. Binary Units of Measurement The gap between units when using binary values is always 1,024 . For example, there are 1,024 bytes in 1 kibibyte and 1,024 kibibytes in 1 mebibyte . To convert between binary units , divide by 1,024 when moving to a larger unit (e.g. 4,096 kibibytes is 4 mebibytes ) and multiply by 1,024 when moving to a smaller unit (e.g. 55 pebibytes is 55,296 tebibytes ). For example, 34 KiB is the same as 34,816 MiB or 35,651,584 GiB . Bi nary values have a prefix ending in ‘ bi ’ , such as ki bi byte or me bi byte. Computer scientists often use the binary system of measurement because the storage size is technically more accurate . Q uesto's Q uestions 1.7 - Units of Measurement: 1 a. Create a table or list that clearly shows the relationship between values from bit up to petabyte for the metric (decimal) measurement system . [4 ] 1 b. Create another table to display the binary measurement system from bit to pebibyte . [4 ] 2. Make the following conversions and show your working out . [2 each ] a. 40 megabytes into kilobytes . b. 8500 gigabytes into terabytes . c. 100 mebibytes into kibibytes . d. 854,016 mebibytes into gibibytes . e. How many bytes are there in 3 megabytes ? f. How many bytes are there in 3 mebibytes ? 1.6 - Hardware Troubleshooting 1.8 & 1.9 - Number Systems Topic List

1.3 - Computer System Types Exam Board: OCR Specification: 2016 - Unit 1 Different types of computer system are available to purchase and use, each with their own benefits , drawbacks and typical functions . Desktop A computer suitable for use at an ordinary desk. They are bulky and not so easy to move . Individual components (e.g. graphics card) can be upgraded over time . Desktops are versatile , they allow the user to carry out a range of activities , including document creation, data manipulation, game playing, design and communication facilities for personal or business purposes. Tablet / Laptop A small and portable type of computer. Many modern laptops can also fold back , effectively turning them into a tablet with a screen-based virtual keyboard . They can perform many of the functions of the traditional PC, but the screen size can be restrictive , especially if several documents need to be open at the same time. Because it can be transported through public spaces, loss or theft is more likely. Smartphone Embedded Systems Smartphones can be used to run a range of applications including email, social media, videos and music. However, they can negatively affect social interaction (e.g. by using them and ignoring people around you) and reduce spatial awareness when being used. Security is another issue as they can be easily lost or stolen . Security software for phones is not as secure as other computer systems so sensitive data should not be held on smartphones. An embedded system is when a smaller computer system is installed within a larger device , such as a washing machine, traffic light or car. Embedded systems have a dedicated purpose and often run in real-time . The internet of things (IoT) describes a global network of connected objects that were previously 'dumb', such as smart bulbs, smart plugs and thermostats. Mainframe Mainframes are huge and very powerful computers that are reliable . Mainframes are used to process large amounts of data and can be used to solve scientific and engineering problems that require complex calculations with large datasets (e.g. weather forecasting or scientific simulations). Mainframes are reliable and secure because they have large backup capabilities . Mainframes are very expensive and require teams of experts to oversee them, and so are used only by organisations that need to process very large amounts of data quickly, such as banks and airlines . Quantum These are still experimental and in development . They work with quantum bits ( qubits ), which, unlike binary, are not limited to just two states (0 or 1). Qubits represent atomic particles, which can be in several different states at the same time . A fully working quantum computer would potentially be able to process data and perform calculations millions of times faster than currently available computers. Q uesto's Q uestions 1.3 - Computer System Types: 1. For each type of computer system , make a list of benefits , drawbacks and possible uses . a. Desktop [6 ] b. Tablet / Laptop [6 ] c. Smartphone [6 ] d. Embedded System [6 ] e. Mainframe [6 ] f. Quantum Computer [6 ] 2. Suggest and justify which type of computer system is most suitable for the following scenarios: a. Updating a spreadsheet while on a train. [3 ] b. Forecasting the next week’s weather. [3 ] c. A PE teacher recording sports day race times. [3 ] d. Playing a new video game on maximum settings. [3 ] 1.2 - Computer Components Topic List 1.4 - Connectivity

3.3 - Network Characteristics Exam Board: OCR Specification: 2016 - Unit 1 Network Topologies Network topology refers to the arrangement of computer systems on a network . Devices in a network topology diagram are often called ' nodes ' . Client-Server Network Clients make requests to a server , the server manages that request and responds . For example, if the user (client) makes a request to access www.csnewbs.com to a web server . Large services like Amazon and Google will need very powerful servers to handle millions of requests a second. The client is completely dependent on the server to provide and manage the information. The server controls network security , backups and can be upgraded to manage higher demand. Disadvantages: Large amounts of traffic congestion will cause the network to slow down . If a fault occurs with the server then the whole network will fail . IT technicians may be required to manage and maintain the network . Malware , such as viruses, can spread quickly across the network. Peer-to-Peer Network For peer-to-peer networks , data is shared directly between systems without requiring a central server . Each computer is equally responsible for providing data. Peer-to-peer is optimal for sharing files that can then be downloaded. Bus Topology The nodes are connected to a bus (a central cable which transfers all data on the network). How it works: The bus transfers data packets along the cable . As the data packets arrive at each computer system, the computer checks the destination address contained in the packet to see if it matches its own address . If the address does not match , the computer system passes the data packet to the next system . If the address of the computer system matches the destination address in the data packet, it is accepted and processed. At both ends of the cable are terminators to mark the end of the bus. Advantages: Because of the simple layout, it is easy to attach another system to the main cable without disrupting the whole network . A bus topology is quick to set up once the main cable has been established making it optimal for temporary networks . A bus topology is cost-effective because it usually contains less cabling than other topologies and requires no additional hardware (like a hub or switch). Disadvantages: Poor security as data packets are passed on to each system on the network. Data collisions are likely - this is when two systems attempt to transfer data on the same line at the exact same time. Resending the data wastes time and slows down the network . The main cable will only have a limited length which can become crowded and slows network speed as more systems are attached. The main cable must also be terminated properly . Token Ring Topology In a token ring network , computer systems are connected in a ring or a loop. How it works: A token (small data packet) is sent around the ring in one direction, being passed from one computer system to the next. A computer seizes the token and includes its own data when it transfers data. As the token arrives at each computer system, the system checks the destination address contained in the packet to see if it matches its own. If the addresses match, the computer processes the data otherwise it ignores it. Advantages: Data collisions are avoided as data packets are transmitted in one direction around the ring. Attaching more systems to a ring topology won't affect the transfer speed as much as other layouts like a bus topology because the data is transferred at a consistent speed . Disadvantages: If any system on the network fails then the whole network fails as the loop is broken and data can't be transferred to all systems. To add a new system to a ring topology the network must be temporarily shut down . Star Topology In a star network , each computer system is connected to a central node: a hub or switch . How it works: Each node is connected to the central node (usually a hub or switch ) and transfers its data packets here. The hub/switch looks at the destination address and transfers the packets to the intended computer only. Advantages: A star topology has improved security because data packets are sent directly to and from the hub / switch in the centre and not necessarily all devices like in a bus or ring topology. New systems can be attached directly to the central system so the network doesn't need to be shut down . System failures of attached computers won't usually cause complete network failure. Transfer speeds are generally fast in a star topology as there are minimal network collisions . Disadvantages: Extra hardware (the hub or switch) is required to be purchased, installed and maintained. If the central system (the hub or switch) fails then the whole network will be unusable until the error is fixed. Mesh Topology In a mesh network, each computer system is connected to every other computer system . How it works: Data packets are transferred to the destination address along the quickest path, travelling from node to node. If a pathway is broken, there are many alternative paths that the packets can take. Advantages: If one cable or system fails then data packets can take an alternative route and still reach the destination address. Because of the large possible number of systems and connections, a mesh topology can usually withstand large amounts of data traffic . New systems can be added to the network without disrupting the entire topology . Disadvantages: Because of the possibly large amount of cables required (especially in a complete mesh topology) this network layout can be expensive to install and maintain . Redundant cabling should be avoided - this is when cables are connected between systems that won't ever need to communicate . Configuration Before a computer system can use a network, three pieces of information must be configured (set up) correctly. IP Address An IP address is used to uniquely identify computer systems on a network , allowing communication between them. An example of an IP address is 195.10.213.120. Default Gateway When data is to be sent from one network to another , it must be sent through a default gateway . This default gateway is usually a router that connects the local network to another network . On many home networks , the default gateway will use the same private IP address : 192.168.1.1 Network managers can use automatic configuration which is quicker and easier to set up . A new device can connect to and use a network automatically , such as free WiFi in an airport. Network managers can also set manual configuration which improves security as new devices can’t be used until the addresses have been configured by a technician . This stops unauthorised devices from connecting to the network. Subnet Mask Subnetting is the act of dividing a physical network into smaller 'sub' networks (known as subnets ) . This helps to reduce traffic and means that users can externally access parts of a network (e.g. emails from home) without having to open the entire network. A subnet mask is used to define these subnets . The mask is used to determine the start and end address of each IP address in a subnet. A common subnet mask is 255.255.255.0 as making the first 3 sections full restricts the fourth section to 256 unique values. For example 113.12.14.230 and 113.12.14.157 are in the same subnet but 114.12.14.127 wouldn't be. Q uesto's Q uestions 3.3 - Network Characteristics: 1 a. Describe how peer-to-peer networks and client-server networks function. 1b. Give one use for both types of network. 2a. Draw and label a diagram for all 6 network topologies . 2b. Describe 2 advantages and 2 disadvantages of each network topology . 3 . What is an IP address ? Why is it necessary for networks? 4. Describe what is meant by a default gateway . 5a. What is subnetting ? 5b. What is the purpose of a subnet mask ? 5c. State a common subnet mask . How many unique devices can be used on a network with this subnet mask? 6. Describe 1 reason why a network manager may use automatic configuration and 1 reason why they may use manual configuration . Advantages: The network can be controlled centrally from the server to easily backup data and update software . Hardware, software and resources can be shared across the network, such as printers, applications and data files . The network allows for improved scalability , meaning more clients can be easily added to the central server . Disadvantages: Without a dedicated server there is no central device to manage security or backups . Backups must be performed on each individual system. Computer performance will decrease with more devices connected to the network, especially if other machines are slow. Advantages: This is a simpler network than client-server to set up as no server is required . Clients are not dependent on a server . Perfect for quickly sharing files between systems , such as downloading media files. 3.2 - Virtualisation Topic List 3.4 - Connection Methods

3.1 - Server Types Exam Board: OCR Specification: 2016 - Unit 1 What is a server? A server is a powerful dedicated system on a network . It requires increased memory , storage and processing power than traditional computer systems to fulfill its role across the network. Servers need to be scalable - this means they must be adaptable and able to efficiently manage the needs of connected systems if more are added or some are removed . Servers have different roles so a company may use multiple , separate server types within their organisation, each with a specific purpose . Having separate servers is costly but beneficial as if one loses connection , others may still be usable . Also a server will be more efficient if it is only managing one resource (e.g. printers) at a time . File Server A file server centrally stores and manages files so that other systems on the network can access them. The server provides access security , ensuring that only users of the appropriate access level can access files. File servers can be used to automatically backup files , as per the organisation's disaster recovery policy. Using a file server frees up physical storage space within a business and can provide printing services too. Printer Server These servers control any printers on a network and manage printing requests by sending the document to an appropriate printer. Print servers use spooling to queue print jobs so that they are printed when the printer is ready. If a fault occurs with a certain printer, work can be automatically diverted to another available printer. Application Server These servers allow users to access shared applications on a network. All users will be able to access common applications like email software or word processing, but the server will also restrict certain applications to those with invalid access levels (such as hiding financial databases from employees outside of the finance department). Application updates can be simply deployed to the application server only , avoiding individual updates for each system and saving a lot of time . Installers can be hosted on an application server, allowing the software to be easily installed on other connected machines . Database Server These servers manage database software that users on the network can access and use to manipulate data . Data held on the server will be stored in a database accessible from multiple connected computers . The data can be modified using query languages such as SQL. Storing data on a database server, rather than individual computers, is more reliable . A database server for a business also allows for scaling - for example, the database can be increased in size if the customer base grows. Web Server A web server manages HTTP requests from connected devices to display web pages on web browsers . A request (e.g. csnewbs.com) is sent to the web server. The server contains a list of known URLs and their matching IP addresses . The server contacts the server where the web page is held and delivers the web page to the client . Mail Server These servers send and receive emails using email protocols (SMTP & POP) allowing email communication between other mail servers on other networks. The server makes sure emails are delivered to the correct user on the network. Email servers can store company address books making internal communication easier for organisations. The server may have anti-spam functions to reduce junk mail. Hypervisor A hypervisor allows a host machine to operate virtual machines as guest systems. The virtual machines share the resources of the host , including its memory, processing power and storage space. This type of technology is called virtualisation . The guest machines are isolated so if one failed, the other guests and the hosts are not affected - demonstrating good security . The hypervisor optimises the hardware of the host server to allow the virtual machines to run as efficiently as possible. Q uesto's Q uestions 3.1 - Server Types: 1a. What is a server ? Why does it need to be scalable ? [2 ] 1b. Give two reasons why a company may use multiple , separate servers . [2 ] 1c. State the 7 types of server . [1 each ] 2. A medium-sized animation company working on a movie are considering buying a server. Describe each type of server and the different roles they have. a. File Server b. Printer Server c. Application Server d. Database Server e. Web Server f. Mail Server g. Hypervisor [4 each ] 3. What type of technology does a hypervisor use to control multiple virtual machines? [1 ] 2.7 - Protocols Topic List 3.2 - Virtualisation

2.3: Utility Software Exam Board: OCR Specification: 2016 - Unit 1 What is utility software? Utility software are dedicated programs used for the maintenance and organisation of a computer system. Antivirus Software Antivirus software is used to locate and delete viruses on a computer system. The antivirus scans each file on the computer and compares it against a database of known viruses . Files with similar features to viruses in the database are identified and deleted . There are thousands of known viruses but new ones are created each day by attackers so antivirus software must be regularly updated to keep systems secure. Other roles of an antivirus: Checking all incoming and outgoing emails and their attachments . Checking files as they are downloaded . Scanning the hard drive for viruses and deleting them . Firewall A firewall manages incoming and outgoing network traffic . Each data packet is processed to check whether it should be given access to the network by examining the source and destination address . Unexpected data packets will be filtered out and not accepted to the network. Defragmentation As files are edited over time they will become fragmented - this is when the file is split into parts that are stored in different locations on the hard disk drive . Files that are fragmented take longer to load and read because of the distance between the fragments of the file. Defragmentation software is used to rearrange the file on the hard disk drive so that all parts are together again in order. Defragmentation improves the speed of accessing data on the hard disk drive. Compression Compression is used to decrease the size of a file . This is beneficial as more files can be stored on a storage device if the size has been reduced. Compressed files can be transferred faster across a network because they are smaller in size . Monitors, Managers & Cleaners Other roles of a firewall include: Blocking access to insecure / malicious web sites . Blocking certain programs from accessing the internet . Blocking unexpected / unauthorised downloads . Preventing specific users on a network accessing certain files . Monitoring network ports . System monitors check the resources of a computer and display how much CPU time and memory current applications are using. Task managers allow a user to close processes and applications if they have stopped responding or if one is using too many resources. Press Ctrl + Alt + Delete on any Windows computer to open Windows Task Manager which is a system monitor and task manager tool. A disk cleaner is used to scan a hard disk drive and remove unused files . This is used to free up space on the hard drive. A disk scanner will scan a hard disc for any errors and attempt to repair them . Backing Up Data A backup is a copy of data that can be used if the original data is corrupted or lost . Backups of all data should be made regularly and stored in an alternative location . Alternatively, imaging (also known as disk cloning ) creates an identical image of a storage drive to be stored in a different location . Q uesto's Q uestions 2.3 - Utility Software: 1. What is the purpose of utility software ? [1 ] 2a. Describe how antivirus software works. [ 2 ] 2b. Describe 3 further roles of antivirus software . [ 3 ] 3a. What is the purpose of a firewall ? [ 2 ] 3b. Describe 3 further roles of a firewall . [ 3 ] 4a. Describe what is meant by defragmentation . [ 2 ] 4b. Explain why defragmentation software is used . [ 2 ] 5. Describe 2 benefits of using compression . [ 2 ] 6a. Explain why system monitor / task management software could be used . [ 2 ] 6b. Explain the purpose of disk cleaners and disk scanners . [ 2 ] 7a. Explain what a backup is and why they are are important. [ 2 ] 7b. Describe what imaging is. [ 2 ] 2.2 - Applications Software Topic List 2.4 - Operating Systems