Search CSNewbs

The first part of a quick guide to the basics of Python aimed at Key Stage 3 students. Learn about comments and printing. Python - #2 - Variables 1. Number Variables A variable is a value that can change . Imagine there are 20 biscuits in a jar. Then I eat one. Now there are only 19. You must state what the value of a variable is before it is used . e.g. biscuits = 20 Task 1 - Create a new Python program and save the file as 2-Variables.py Create a variable called sweets and give it the value 15. Then print sweets. Variable names cannot have spaces . You can use underscores if you want, e.g. num_of_eggs When you are printing variables, you don't put them in speech marks . Otherwise, it will print the variable name and not the value. 2. String Variables A string is a programming term for a collection of characters . When you are giving a variable a string value, it must be written in speech marks . Remember when you print the variable however, it is never printed in speech marks . Task 2 - Create a variable called name and give it the value of your name. Then print the name variable. 3. Using Variables in a Sentence When we have printed the variables so far, they have not been very informative! You can print variables together with sentences so that they mean more. Use a comma ( , ) between variables and sentences . Task 3 - Use the pictures to help you add commas and sentences to your program to be more informative. 4. Using Variables Together You can print more than one variable together in the same sentence by separating them with sentences and commas . If this doesn't work, double-check your program has a comma between each variable and sentence . Task 4 - Type a new print line that uses both your name and your sweets variables together. Use the image to help you. Challenge Programs Use everything that you have learned on this page to help you create these programs... Challenge Task 1 - Funny Animals Create a new Python program. Save it as ' 2-FunnyAnimals.py ' Add a comment at the top with your name and the date. Create a variable for a colour and give it a value (e.g. "blue") Create a variable for an animal and give it a value (e.g. "horse") Print a funny sentence that uses both variables. BONUS : Try to use only one print line. BONUS : Try to use only three lines in total . Remember: Break up variables in a print line by using commas. When you run it, it could look something like this: Challenge Task 2 - Funny Sentence Create a new Python program. Save is as ' 2-FunnySentence.py ' Add a comment at the top with your name and the date. Write a program that uses three variables, an adjective (descriptive word), a number and an animal. Print a funny response using all variables. BONUS : Try to use only one print line. BONUS : Try to use only four lines in total . Remember: Break up variables in a print line by using commas. When you run it, it could look something like this: <<< #1 The Basics #3 Inputs >>>

Learn about different types of human computer interaction (HCI) such as audio, movement / gesture, touch and visual (command line and graphical user interface (GUI)). Based on Unit F160 (Fundamentals of Application Development) for the OCR Cambridge Advanced National in Computing (H029 / H129) (AAQ - Alternative Academic Qualification). Qualification: Cambridge Advanced National in Computing (AAQ) Unit: F160: Fundamentals of Application Development Certificate: Computing: Application Development (H029 / H129) 5.1.1 - Types of Human-Computer Interaction Watch on YouTube : Human-Computer Interaction Human-computer interaction (HCI) refers to the ways in which users engage with computers and is an important factor that must be considered when designing and developing an application . For each type of HCI you need to know its purpose , devices on which it is used , its advantages and disadvantages and how client requirements may affect its use . Human-Computer Interaction Types of User Interaction Audio allows users to interact with a system using voice commands . Body movements or gestures (e.g. hand waves or head turns ) can control or interact with applications . Touch allows users to interact by tapping , swiping , dragging or pinching directly on a screen . Graphical user interfaces ( GUIs ) provide a visual interface using windows , icons , buttons and menus . Command-line interfaces ( CLIs ) only allow interaction with the system by typing text commands into a terminal or shell . Q uesto's Q uestions 5.1.1 - Types of Human-Computer Interaction: 1. A company selling toys wants to create an app to advertise its latest products . Justify the suitability of each user interaction type for the company's app . [5 ] 2. Compare the GUI and CLI visual interaction methods, including their advantages and disadvantages . [8 ] 3. Explain when the audio interaction method would be appropriate . [ 3 ] In 2012 Milwaukee County Zoo started giving iPads to orangutans so they could use the touchscreen to draw pictures . D id Y ou K now? 4.3 - Decomposition Methods Topic List 5.1.2 - Types of Device

Learn about 11 key attributes that a respected and successful member of staff should develop in a work environment. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification. 4.3 - Personal Attributes Exam Board: OCR Specification: 2016 - Unit 1 Any employee in an organisation must demonstrate positive qualities that makes them a useful worker . The following are some of the key attributes that a successful employee of an IT organisation should have. Self-motivation: Workers must be able to motivate themselves to produce high-quality work . They must arrive to work willing to face new challenges and retain a good attitude even when faced with difficulties. Leadership: Managers must show good leadership skills by respecting members of their team so that they are motivated and produce good work. A leader must delegate tasks and take responsibility for negative outcomes. Respect: Respect must be shown at all times to other members of staff and to customers . Employees should be polite and patient when dealing with requests and uphold the company's values . Dependability: Managers must be able to depend on their employees to complete work to the best of their ability and complete it on time . Employees should also be trustworthy and reliable to work on tasks independently. Punctuality: Arriving to work on time is important and shows a commitment to your job . Employees must show up on time to meetings and scheduled events so they don't miss out or upset others. Problem Solving: An employee must be able to look at a problem from different angles and perspectives in order to solve it. Workers must use logic and learn from previous mistakes . Determination: Workers should be focused on their job role and not give up on challenging tasks. Workers must be prepared to work on a dedicated task until it is fully completed . Independence: Workers should be able to work alone on tasks and not rely on other members of staff . They should be confident in finding a solution to a problem independently. Time Management: Most tasks will have a deadline and it is the worker or team's responsibility to ensure all work is completed before that date. Workers must be organised and plan ahead in case of unforeseen circumstances. Team Working: Most modern IT jobs involve group work , either within the office or using online communication across different sites. Workers must cooperate with their peers, share ideas and work together to complete tasks on time. Numerical Skills: Maths skills are required in IT jobs to ensure that jobs are completed accurately and within the budget . Workers may use calculators or spreadsheets to prevent mistakes. Verbal Skills: Spoken communication is a huge part of most jobs, whether that be face-to-face , on the phone or through video calls . Workers must be polite to customers and respectful to co-workers , using appropriate language at all times. Planning & Organisation: To ensure all deadlines are met , teams must carefully plan who will complete each task and by when. Companies must be well organised so that departments can work together and share information when necessary. Q uesto's Q uestions 4.3 - Personal Attributes: The Job Roles section (4.5 ) may help you answer these questions. 1. A games company are looking to hire a new manager to oversee the development of their next video game. Describe 4 personal attributes that the manager should have. [10 ] 2. A software company that develops web browsers is hiring a new programmer . Describe 4 personal attributes that the programmer should have. You must not describe the same attributes as Q1 . [10 ] 3. An animator is required at a large design and movie production studio. Describe 4 personal attributes that the animator should have. You must not describe the same attributes as Q1 or Q2 . [10 ] 4.2 - Communication Technology Topic List 4.4 - Ready for Work

Learn about business systems used by IT companies including MIS, SOP, CRM and help desk. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification. 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

Learn about the three factors that affect computer performance - cache memory, clock speed and the number of cores. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 1.2: CPU Performance Exam Board: OCR Specification: J277 Watch on YouTube : Clock Speed Cache Memory Number of Cores The performance of a computer system is affected by three main factors: Cache Memory What is cache memory? Cache memory is temporary storage for frequently accessed data . How does cache memory improve performance? Cache memory is closer to the CPU than RAM , meaning that it can provide data and instructions to the CPU at a faster rate . A computer with more cache memory (e.g. 8GB instead of 4GB) should have a higher performance because repeatedly used instructions can be stored and accessed faster . What is the limitation of cache memory? Cache memory is costly, so most computers only have a small amount . Clock Speed What is clock speed? Clock speed is the measure of how quickly a CPU can process instructions . Clock speed is measured in Gigahertz (GHz) . A typical desktop computer might have a clock speed of 3.5 GHz . This means it can perform 3.5 billion cycles a second . How does clock speed improve performance? The faster the clock speed, the faster the computer can perform the FDE cycle resulting in better performance because more instructions can be processed each second . How does overclocking and underclocking affect performance? Default clock speed: 3.5 GHz Underclocking Overclocking 3.9 GHz 3.1 GHz Overclocking is when the computer's clock speed is increased higher than the recommended rate. This will make the computer perform faster, but it can lead to overheating and could damage the machine . Underclocking is when the computer's clock speed is decreased lower than the recommended rate. This will make the computer perform slower but will increase the lifespan of the machine . Number of Cores What is a core? A core is a complete set of CPU components (control unit, ALU and registers). Each core is able to perform its own FDE cycle . A multi-core CPU has more than one set of components within the same CPU. How does the number of cores improve performance? In theory, a single-core processor can execute one instruction at a time , a dual-core processor can execute two instructions, and a quad-core can execute four instructions simultaneously . Therefore, a computer with more cores will have a higher performance because it can process more instructions at once . What are the limitations of having more cores? If one core is waiting for another core to finish processing, performance may not increase at all. Some software is not written to make use of multiple cores , so it will not run any quicker on a multi-core computer. Q uesto's Q uestions 1.2 - CPU Performance: Cache Size & Levels 1a. What is cache memory ? [ 2 ] 1b. Describe two ways that more c ache memory will mean performance is higher . [ 4 ] 1c. Explain why most computers only have a small amount of cache memory. [ 1 ] Clock Speed 2a. What is clock speed ? What is it measured in? [ 2 ] 2b. Explain how a higher clock speed improves performance . [ 2 ] 2c. Explain the terms 'overclocking ' and 'underclocking ' and explain the effects of both on the performance of a computer. [ 4 ] Number of Cores 3a. What is a core ? [ 2 ] 3b. Explain why a quad-core processor should have a higher performance than a dual-core processor . [ 3 ] 3c. Explain two reasons why having more cores doesn't necessarily mean the performance will be better . [ 2 ] 1.1b - Registers & FE Cycle 1.3 - Embedded Systems Theory Topics

Learn about key mnemonics used in assembly language and how very simple programs can be created. Assembly Language Assembly language is a low-level programming language - it is closer to machine code (binary) than high-level programming languages like Python. Assembly language uses mnemonics (abbreviations of commands) to signify instructions; for example, input is written as INP and output is written as OUT . Little Man Computer is a representation of assembly language . This simulator will help you understand assembly language and allow you to check if your instructions are correct. Assembly Language Mnemonics INP (Input) INP is used to input a number . The number is temporarily stored in the accumulator . OUT (Output) OUT is used to output the number currently stored in the accumulator . STA (Store) STA stores the value that is currently in the accumulator . It can be used to assign a value to a variable. ADD (Addition) ADD is used to add a number to the value currently stored in the accumulator. SUB (Subtraction) SUB takes away a number from the value currently stored in the accumulator. LDA (Load) LDA is used to load the value of a stored variable back into the accumulator . BRZ (Branch if Zero) BRZ is used to loop only if the value in the accumulator is currently 0 . BRP (Branch if Positive) BRP is used to loop only if the value in the accumulator is currently positive (including 0). BRA (Branch Always) BRA is used to loop continuously . HLT (Halt) HLT will stop running the program . Every program MUST have a HLT command. DAT (Data Definition) DAT must be used to define a variable name (and / or set it with a starting value). Data definitions must be written at the end of the instructions . Peter Higginson's Little Man Computer simulation Examples of Simple Assembly Language Programs #1 - Input & Output Program Purpose: Input a number, store the number as a variable called Number1 and output the number. 1. Lets the user input a number 3. Outputs the value in the accumulator - which will be the number that was just inputted. 5. Defines a variable called 'Number1'. This has to be at the end of the program and you must write the variable name first, not the command first. INP STA Number1 OUT HLT Number1 DAT 2. Stores the number in a variable named 'Number1' - there must be no spaces in a variable name. 4. Halts (stops) the program. Type these instructions line by line into the Little Man Computer simulator to see how it works. #2 - Addition Program Purpose: Input and store two numbers. Add them together. Output the total. 1. Lets the user input a number 3. Lets the user input another number 5. Adds number1 to the value in the accumulator (which is currently number2 as you just inputted it). 7. Halts the program. Type these instructions line by line into the Little Man Computer simulator to see how it works. Then change the program to subtract the number instead. INP STA Number1 INP STA Number2 ADD Number1 OUT HLT Number1 DAT Number2 DAT 2. Stores the inputted number in a variable named 'Number1'. 4. Stores the inputted number in a variable named 'Number2'. 6. Outputs the value in the accumulator (which is now number1 added to number2. 8. & 9. The two variables Number1 and Number2 are defined on separate lines. #3 - Load in Order Program Purpose: Input and store three numbers. Load and output them in the order that they were entered. 1. - 6. Lets the user input three numbers and immediately stores each one as they are entered. 8. Now that Number1 has been loaded into the accumulator, this value is outputted. 13. Halts the program. Type these instructions line by line into the Little Man Computer simulator to see how it works. Let the user input a fourth number and output this fourth number last . INP STA Number1 INP STA Number2 INP STA Number3 LDA Number1 OUT LDA Number2 OUT LDA Number3 OUT HLT Number1 DAT Number2 DAT Number3 DAT 14. - 16. The three variables Number1, Number2 & Number3 are defined on separate lines. 9. - 12. Number2 is loaded and output then Number3 is loaded and output 7. Once all three numbers have been inputted and stored, the first number is loaded back into the accumulator. #4 - Branching Program Purpose: Input and store two numbers. Output the largest number. (Branching required). 1. - 4. Lets the user input two numbers and immediately stores each one as they are entered. 7. BRP is 'Branch is Positive'. If the result of Number1 - Number2 is positive then the program will jump to line 11. You can write any value instead of 'loop', such as 'jump' or 'break'. If the result is not positive it will continue to the next line. 11. - 13. The program will jump to line 11 if the result of Number1 - Number2 is positive. This means that Number1 is larger than Number2 so Number1 is loaded and output then the program is halted. INP STA Number1 INP STA Number2 LDA Number1 SUB Number2 BRP loop LDA Number2 OUT HLT loop LDA Number1 OUT HLT Number1 DAT Number2 DAT 5. & 6. Loads Number1 and subtracts Number2 from it. 8. - 10. The program will continue to line 8 if the result of Number1 - Number2 is not positive. Because the result is a negative number, this tells us that Number2 is larger than Number1. So we load Number2, output it because it is bigger, then halt the program. 14. - 15. The variables Number1 & Number2 are defined on separate lines. Type these instructions line by line into the Little Man Computer simulator to see how it works. Change the program so that the smallest number is output .

Learn about applications, utility software, open source and closed source, translators including interpreters, compilers and assemblers, stages of compilation (lexical analysis, syntax analysis, code generation and optimisation) and linkers, loaders and libraries. Based on the OCR H446 Computer Science A-Level specification. Exam Board: OCR A-Level 2.2 - Applications Generation Specification: Computer Science H446 Watch on YouTube : Application software Utilities Open & closed source High & low level language Translators Stages of compilation Linkers, loaders & libraries This topic explores key types of software and how they support computer systems and users . It explains different kinds of applications , utilities , translators and compares open and closed source software . Another important concept is compilation , with knowledge required of its different stages , as well as linkers , loaders and software libraries . Applications Software Applications software allows users to carry out productive or creative activities such as document editing , data analysis , communication or media creation . Common examples include word processors (e.g. Microsoft Word or Google Docs ), spreadsheets (e.g. Excel or Sheets ), database management systems (e.g. Access ), web browsers (e.g. Chrome or Safari ) and graphics editors (e.g. Photoshop ). Applications can be general-purpose , serving many uses , or special-purpose , created for a specific function like payroll or medical record management . Utilities Utility software is system software designed to maintain , optimise and manage a computer’s performance , often running in the background to support the operating system . Examples include security tools like an antivirus , backup , compressors , disk management utilities and defragmenters . Defragmentation is the process of reorganising files on a hard drive so that parts of each file are stored together in contiguous blocks , improving access speed . Open Source & Closed Source Open source software has its source code (the actual code written by its developers ) made publicly available , allowing users to view , modify and share it freely . An open source licence encourages collaboration , transparency and community-driven improvement . However, it may lack official technical support or guaranteed updates . Closed source software has its source code private , restricting modification and redistribution . It is usually sold commercially with paid licences , regular updates and dedicated technical support . Bug fixes and quality assurance are out of the user's control , being managed by the developer . Support may end without warning . High & Low Level Languages Programming languages can be split into high-level and low-level , based on how close they are to the computer’s hardware . High-level languages are easier to read and write , while low-level languages give direct control over hardware but are harder to use . High-level languages like Python or Java are similar to natural human language, making them easy to write , understand, and debug . Low-level languages include machine code (binary ) and assembly language but are written for specific processor architecture . Translators Translators are programs that convert source code written in one programming language into another form that the computer's CPU can understand - typically machine code (binary ). An assembler translates assembly language into machine code that the CPU can execute directly . An interpreter translates and executes high-level code in a line-by-line method, stopping when an error occurs . A compiler translates the entire high-level program into machine code before execution , producing an executable file . Stages of Compilation Compilation is a complicated process to convert high-level program code into machine code . It consists of four key stages : Lexical analysis breaks the source code into tokens , such as keywords , identifiers and operators . Spaces and comments are removed and a symbol table of identifiers is created. Syntax analysis checks that the token sequence follows the grammatical rules of the programming language , building an abstract syntax tree . Code generation converts the abstract syntax tree into object code (unfinished machine code ) the CPU can understand . Code optimisation improves the efficiency of the generated code , for example by reducing redundant instructions or improving execution speed . Libraries, Linkers & Loaders Compilation also requires additional programs, such as a linker and loader and the use of libraries . A library is a collection of pre-written code created by other programmers that contains useful routines and functions which can be reused in a program. A linker combines object code and libraries , resolving references so that a final executable file can be created . A loader copies an executable file from secondary storage into RAM , ready for execution by the processor . Q uesto's K ey T erms Applications: database, word processor, web browser, graphics manipulation, spreadsheet software, presentation software Utilities: defragmentation, system cleanup, file manager, device driver, security tools Open & Closed Source: source code, open source, closed source Translators: assembler, interpreter, compiler, machine code Stages of Compilation: lexical analysis, token, syntax analysis, abstract syntax tree, code generation, code optimisation, library, linker, static linking, dynamic linking, loader D id Y ou K now? Grace Hopper , a US Navy rear admiral , is credited with creating one of the first compilers in 1952 and coining the term ' compiler '. She also helped develop the languages FLOW-MATIC and later COBOL , which is still used today . 2.1 - Systems Software A-Level Topics 2.3 Software Development

Learn about how to convert between the denary (decimal), binary and hexadecimal number systems. Based on the 2020 Eduqas (WJEC) GCSE specification. 4.1: Number Systems Exam Board: Eduqas Specification: 2020 What is binary? By now you should know that computer systems process data and communicate entirely in binary . Topic 1.4 explained different binary storage units such as bits (a single 0 or 1), nibbles (4 bits) and bytes (8 bits). Binary is a base 2 number system. This means that it only has 2 possible values - 0 or 1 . Because binary is a base 2 number system, binary numbers should be written out with a 2 after them, like this: 10101002 What is denary? Denary (also known as decimal ) is the number system that you've been using since primary school. Denary is a base 10 number system. This means that it has 10 possible values - 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 . Because denary is a base 10 number system, denary numbers should be written out with a 10 after them, like this: 165 10 How to convert from binary to denary: How to convert from denary to binary: What is hexadecimal? Hexadecimal is a base 16 number system. This means that it has 16 possible values - 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E and F . Because hexadecimal is a base 16 number system, hexadecimal numbers should be written out with a 16 after them, like this: 6E16 Hexadecimal is used as a shorthand for binary because it uses fewer characters to write the same value . This makes hexadecimal less prone to errors when reading or writing it , compared to binary. For example, 1001111010112 is 9EB16 . Hexadecimal only uses single-character values. Double-digit numbers are converted into letters - use the table on the right to help you understand. How to convert from binary to hexadecimal: How to convert from hexadecimal to binary: Converting from denary to hexadecimal / hexadecimal to denary To convert from denary to hexadecimal or the other way round you must convert to binary first . Denary > Binary > Hexadecimal Hexadecimal > Binary > Denary Use the videos on this page if you need help converting to or from binary. The most common number systems question in exams are from denary to hexadecimal or from hexadecimal to denary so make sure that you practice these conversions. Q uesto's Q uestions 4.1 - Number Systems: 1. Explain why hexadecimal numbers are used as an alternative to binary . Use an example . [ 3 ] 2. Convert the following values from binary to denary : a. 00101010 2 b. 11011011 2 c. 01011101 2 d. 11101110 2 e. 01011111 2 [1 each ] 3. Convert the following values from denary to binary : a. 35 10 b. 79 10 c. 101 10 d. 203 10 e. 250 10 [1 each ] 4. Convert the following values from binary to hexadecimal : a. 11110101 2 b. 01100111 2 c. 10111010 2 d. 10010000 2 e. 11101001 2 [1 each ] 5. Convert the following values from hexadecimal to binary : a. C2 16 b. 8A 16 c. DE 16 d. 54 16 e. F7 16 [1 each ] 6. Convert the following values from denary to hexadecimal : a. 134 10 b. 201 10 c. 57 10 d. 224 10 e. 101 10 [1 each ] 7. Convert the following values from hexadecimal to denary : a. 32 16 b. A5 16 c. 88 16 d. C0 16 e. BE 16 [1 each ] Watch on YouTube Watch on YouTube Watch on YouTube Watch on YouTube Click the banners above to try self-marking quizzes (Google Form) on these topics. Denary to Binary: Binary to Denary: Binary to Hexadecimal: Hexadecimal to Binary: 3.9 Protection Against Threats Theory Topics 4.2 - Signed Binary

Learn what an embedded system is and about different examples of embedded systems. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 2.1: Primary Storage (Memory) Exam Board: OCR Specification: J277 Watch on YouTube : Primary Storage RAM and ROM Virtual Memory Primary vs Secondary Storage Storage in a computer system is split into two categories: Primary Storage: Very quick because it is directly accesse d by the CPU . Typically smaller in storage size . Sometimes called ‘main memory’ . Includes RAM and ROM . Volatile vs Non-Volatile Storage Storage is also split into two types - volatile and non-volatile . Volatile storage is temporary - data is lost whenever the power is turned off . Example: RAM Non-volatile storage saves the data even when not being powered . Data can be stored long-term and accessed when the computer is switched on . Example: ROM Why do Computers need Primary Storage? Primary storage is low-capacity , internal storage that can be directly accessed by the CPU . Program instructions and data must be copied from the hard drive into RAM to be processed by the CPU because primary storage access speeds are much faster than secondary storage devices like the hard drive. Types of Primary Storage (Memory) Random Access Memory (RAM) Read-Only Memory (ROM) RAM is volatile (temporary) storage that stores all programs that are currently running . RAM also stores parts of the operating system to be accessed by the CPU. RAM is made up of a large number of storage locations, each can be identified by a unique address . ROM is non-volatile storage that cannot be changed . ROM stores the boot program / BIOS for when the computer is switched on. The BIOS then loads up the operating system to take over managing the computer. RAM ( R andom A ccess M emory) ROM ( R ead O nly M emory) Virtual Memory Programs must be stored in RAM to be processed by the CPU . Even if there is insufficient space in RAM for all programs the computer can use the hard disk drive (HDD ) as an extension of RAM - this is called virtual memory . If new data is needed to be stored in RAM then unused data in RAM is moved to the hard drive so the new data can be transferred into RAM . If the original data is required again, it can be moved back from virtual memory into RAM . Using virtual memory is beneficial because it allows more programs to be run at the same time with less system slow down . Secondary Storage: ( Section 2.2 ) Slower because it is not directly accessed by the CPU . Typically larger in storage size . Used for the long-term storage of data and files because it is non-volatile . Includes magnetic , optical and solid state storage. Q uesto's Q uestions 2.1 - Primary Storage (Memory): 1. Describe the differences between primary and secondary storage . [ 6 ] 2. Explain the difference between volatile and non-volatile storage . State an example of both types. [ 4 ] 3. Explain why the computer requires primary storage . [ 2 ] 4. For each type of memory below, describe it and state what information is stored within it: a . Random Access Memory (RAM) [3 ] b. Read-Only Memory (ROM) [ 3 ] c. Virtual memory [ 3 ] 1.3 - Embedded Systems Theory Topics 2.2 - Secondary Storage

Learn how to play sound files in Greenfoot. Part 5 of the Greenfoot Tutorial for the Eduqas / WJEC GCSE 2016 specification. 5. Play Sounds 1. Check the Sounds Folder Greenfoot Tutorial Sound files must be placed the ' sounds ' folder of your Greenfoot project to be used in the game. In the Component 2 exam of the WJEC / Eduqas 2016 specification , an audio file will be placed in the sounds folder already . For this example game you can download the audio clips to the right and paste them into your sounds folder . Watch on YouTube: Click the audio icon to download a zip folder of the two sound files below . Copy the files into the sounds folder of your Greenfoot project . < Part 4 - Remove Objects 2. Add the playSound Method Add the code to play the sound at the same time as when the collectible object is removed . The name of the file and its extension (e.g. .wav or .mp3 ) must be written in speech marks after the playSound method. Part 6 - The Counter >

Test your ability to create a more complex program in Python based on a given scenario. Perfect for students learning GCSE Computer Science in UK schools. Extended Task 1 Pete Porker's Pork Pie Emporium Hello, Pete Porker here... I need a new program for customer orders at my bakery . I need the customer to enter how many scotch eggs (49p each ), pork pies (85p each ) and quiche tarts (£1.45 ) they want to order. Next, ask them to confirm their choice . If they are not happy , ask the questions again . If they confirm their choice, print a receipt showing their order and total . To make your program better, you should use validation (either while loops or error handling ) to make sure that a user must enter a correct value. Bronze Award --- Welcome to Pete Porker's Pork Pie Emporium --- Scotch eggs are 45p, pork pies are 85p and quiche tarts are £1.49. Enter the number of scotch eggs to buy: 9 Enter the number of pork pies to buy: 7 Enter the number of quiche tarts to buy: 4 ----- You selected 9 scotch eggs, 7 pork pies and 4 quiche tarts. 9 scotch eggs = £4.05 7 pork pies = £5.95 4 quiche tarts = £5.96 ------- Total: £15.96 There are many ways to create this program, but below are some suggestions : Use inputs with int to let the user enter how many of each item they want. Use total variables , e.g. totaleggs = eggs * 0.45 to work out the total cost for eggs, pies and tarts. Set a finalcost variable by adding the total of the three items together. Use dashes and \n (which makes a new line ) inside speech marks to make your program more presentable . Silver Award --- Welcome to Pete Porker's Pork Pie Emporium --- Scotch eggs are 45p, pork pies are 85p and quiche tarts are £1.49. Enter the number of scotch eggs to buy: 5 Enter the number of pork pies to buy: 3 Enter the number of quiche tarts to buy: 6 ----- You selected 9 scotch eggs, 7 pork pies and 4 quiche tarts. ----- Are you happy with this selection? no Okay, enter your choices again. Enter the number of scotch eggs to buy: 6 Enter the number of pork pies to buy: 2 Enter the number of quiche tarts to buy: 7 ----- You selected 6 scotch eggs, 2 pork pies and 7 quiche tarts. ----- Are you happy with this selection? yes Excellent! Here is your receipt : 6 scotch eggs = £2.70 2 pork pies = £1.70 7 quiche tarts = £10.43 ------- Total: £14.83 There are many ways to improve this program and below are some suggestions : Use a while loop to repeat the input stage until the user is happy with their choices. You will need to ask the user if they are happy with the values that were entered and then use an if statement to repeat the loop if they enter 'no '. Gold Award Example solution: --- Welcome to Pete Porker's Pork Pie Emporium --- Scotch eggs are 45p, pork pies are 85p and quiche tarts are £1.49. Enter the number of scotch eggs to buy: 9 Enter the number of pork pies to buy: 35 Sorry you must enter a number between 1 and 20. Starting again... Enter the number of scotch eggs to buy: 9 Enter the number of pork pies to buy: 20 Enter the number of quiche tarts to buy: 7 ----- You selected 9 scotch eggs, 20 pork pies and 7 quiche tarts. ----- Are you happy with this selection? YES Excellent! Here is your reciept: 9 scotch eggs = £4.05 20 pork pies = £17.00 7 quiche tarts = £10.43 ------- Total: £31.48 There are many ways to make this program even better and below are some suggestions : Include validation so that the user can only enter numbers between 1 and 20 . You will need to use if statements and the and operator to do this. You can include additional features to your program such as rounding the number to two decimal places and including coloured text using the Colorama library (which will only work if you are using an online editor like Replit ). You can use the .lower() command when checking if the user is happy with their choices to automatically accept 'Yes' and 'YES '. If you really want to challenge yourself you could consider outputting the receipt in order from most expensive to least expensive , using if statements to check the three values (although that has not been done in this example on the left). Helpful reminders for this task: Inputting Integers While Loops Calculations Rounding Integers ⬅ 12 - Error Handling Extende d Task 2 (Lottery) ➡

Learn about key computing laws including the Data Protection Act (2018) (GDPR), Computer Misuse Act (1990), Copyright Designs and Patents Act (1988), Creative Commons and the Regulation of Investigatory Powers Act. Based on the 2020 Eduqas (WJEC) GCSE specification. 11.2: Legislation Exam Board: Eduqas Specification: 2020 Data Protection Act (2018) In 2018 the European Union introduced GDPR (General Data Protection Regulation ) to protect the privacy of data for people in the EU. The UK matched this by updating the Data Protection Act introduced in 1998 to become the Data Protection Act (2018) . This act protects the data of individuals that is stored on computers and processed by organisations. How the Data Protection Act works: Each person who has their data stored is known as a data subject . An employee within an organisation must be appointed as a data controller and it is they who are responsible for registering with the Information Commissioner . The Information Commissioner is the person in the UK who is responsible for managing several laws , most significantly the Data Protection Act. When registering with the Information Commissioner, the organisation's data controller must be clear on exactly: What information they are collecting, Why it is being collected, What the data will be used for . The six principles of the Data Protection Act state that data must be: 1. Collected lawfully and processed fairly. 2. Only used for the reasons specified. 3. Data must be relevant and not excessive. 4. Data must be accurate and up-to-date. 5. Data must not be stored for longer than necessary, 6. Data must be stored and processed securely. Computer Misuse Act (1990) This act was introduced as computers became cheaper and more common at home and work . The act attempts to stop and punish those who use computers inappropriately . Breaking any of the three principles could result in fines and a jail sentence but only if it can be proved it was done on purpose and not by accident. The Computer Misuse Act (1990 ) includes three main principles : 1. No unauthorised access to data. Example: Hacking a computer system. 2. No unauthorised access to data that could be used for further illegal activities. Example: Accessing personal data to use as blackmail or identity theft. 3. No unauthorised modification of data. Example: Spreading a virus to change data. Freedom of Information Act (2000) This act allows people to request public authorities to release information . Public authorities include local councils , government departments , universities and hospitals . A freedom of information request must be formally submitted in a letter or email and a reply from the organisation is required within twenty days of receiving the request. A simple freedom of information request might be the average response times of the local ambulance service in the past year. Certain requests will not be accepted , such as if processing the request would be too expensive or if it involves sensitive information protected by the Data Protection Act (2018 ). Regulation of Investigatory Powers Act (2000) This act (often shortened to RIPA ) was introduced in response to the increase in both criminal and terrorist activities on the internet, it is used to monitor and access online communication of suspected criminals . If criminal activity is suspected by an individual then this act grants the following powers : Internet Service Providers (ISPs) must provide access to the suspect's online communication , such as emails or social media. Locked or encrypted data may be accessed such as online messages. ISPs could install surveillance equipment or software to track the suspect's online activity . Surveillance may take place to physically track the suspect , e.g. in private vans or by undercover officers in public spaces. Access must be granted to personal information . This act became controversial as its use widened and local councils were using it for minor offences - a Scottish council used the act to monitor dog barking and a council in Cumbria gathered video evidence about who was feeding pigeons . The act has since been changed to only allow the surveillance of crime suspects . Copyright, Designs & Patents Act (1988) This act makes it a criminal offence to copy work that is not your own without the permission of the creator or the copyright holder. This can refer to text, images, music, videos or software. Owning the copyright of an image might not prevent others from copying and using it but this act means that the owner can bring legal proceedings in court to those who have stolen their work . However, it is difficult to trace who has stolen work once it has been uploaded to the internet and copies can easily spread, especially television shows and movies. This act specifically prohibits the following actions: Making copies of copyrighted material to sell to others . Importing and downloading illegally copied material (except for personal use). Distributing enough copyrighted material to have a noticeable effect on the copyright holder . Possessing equipment used to copy copyrighted material , as part of a business. Creative Commons (CC) Licensing A CC licence allows people to share their copyrighted work while still retaining rights to the material . There are different types of licence that specify exactly what can and can't be done to the copyrighted material. For example: An attribution licence allows copyrighted material to be edited and distributed but the original owner must be credited . A non-commercial licence allows copyrighted material to be shared and edited but no profit must be gained through its distribution. CC licences are not automatically given , they must be granted by the copyright owner . To ensure you are not illegally using copyrighted work change the Tools and Licence setting when using Google Images to filter work with CC licenses applied . Telecommunications Regulation Act (2000) This act allows organisations to lawfully monitor communications made online and on the phone by employees while at work . All users of the network should be aware that their communication is being monitored when they are using emails , the internet or telephone calls . The act was introduced to ensure that employees are using the computer systems for the correct purpose , to prevent illegal activity and to monitor staff performance . Codes of Conduct One way that organisations try to ensure that staff are held to professional standards and display appropriate behaviour is to create a code of conduct . This is a set of rules or requirements that employees must follow or they may be punished, such as a temporary ban from the network or being fired. There are two types of codes of conduct: Formal codes of conduct are a set of written rules that clearly state expected behaviour , such as what employees can access online at work . Schools may have this too, and you might have to sign a document at the start of the year before you can use the computers. Informal codes of conduct are used by small organisations where there might not be a written set of rules , but newer employees follow the habits and expectations of senior members of staff. This is harder to monitor but provides a more relaxed working environment. Q uesto's Q uestions 11.2 - Legislation: 1a. State the 6 principles of the Data Protection Act (2018) . [ 6 ] 1b. Explain how the Data Protection Act works . In your answer, you should include definitions of a data subject , the data controller and the Data Commissioner . [ 6 ] 2. Describe the 4 principles of the Computer Misuse Act (1990) . [3 ] 3. Describe the purpose of the Freedom of Information Act (1990) and state an example of a freedom request . [ 3 ] 4a. What is the purpose of RIPA (2000) ? [ 2 ] 4b. Describe 3 actions that RIPA (2000) allows the government / police to do . [ 3 ] 5a. What is the purpose of the Copyright, Designs & Patents Act (1988) ? [ 2 ] 5b. Describe 3 actions that CDPA (1988) prohibits . [ 3 ] 6a. What is a Creative Commons ( CC ) licence ? [ 2 ] 6b. Describe 2 types of CC licence . [ 4 ] 7a. What is the purpose of the Telecommunications Regulation Act (2003) ? [ 2 ] 7b. Describe 3 reasons why this act was introduced . [ 3 ] 8a. What is the purpose of a code of conduct ? [ 2 ] 8b. Describe the difference between formal and informal codes of conduct . [ 2 ] 11.1 - Impacts of Technology Theory Topics