Learn about the different protocols used on networks - HTTP, HTTPS, TCP, IP, Ethernet, WiFi, FTP and SMTP. Based on the 2020 Eduqas (WJEC) GCSE specification. 3.5: Protocols Exam Board: Eduqas Specification: 2020 What is a protocol? A protocol is a set of rules that allow devices on a network to communicate with each other . TCP / IP is actually two separate protocols that combine together. TCP / IP (Transmission Control Protocol / Internet Protocol) TCP is a protocol that allows packets to be sent and received between computer systems. It breaks the data into packets and reassembles them back into the original data at the destination. IP is a protocol in charge of routing and addressing data packets . This ensures data packets are sent across networks to the correct destination . It is also an addressing system - every device on a network is given a unique IP address so data packets can be sent to the correct computer system. HTTP is used to transfer web pages over the Internet so that users can view them in a web browser . All URLs start with either HTTP or HTTPS (e.g. https://www.csnewbs.com). HTTPS is a more secure version of HTTP that works with another protocol called SSL ( Secure Sockets Layer ) to transfer encrypted data . You should see a padlock symbol in the URL bar if your connection to that website is secure. HTTP/HTTPS (Hypertext Transfer Protocol) Ethernet is a protocol for wired connections . Ethernet is used at both the data link and physical layers to describe how network devices can format data packets for transmission. WiFi is the main standard for wireless connections . WiFi is actually a brand name that uses a protocol called IEEE 802.11 . Another wireless standard is Bluetooth , for short-range data transfer. Connection Protocols Transfer Protocols FTP ( File Transfer Protocol ) is used to transfer files across a network. It is commonly used to upload or download files to/from a web server . SMTP ( Simple Mail Transfer Protocol ) is a protocol used to send emails to a mail server and between mail servers . Q uesto's Q uestions 3.5 - Protocols: 1. Describe each of the following protocols . It might be helpful to also draw an icon or small diagram for each one: a. TCP [ 2 ] b. IP [ 2 ] c. HTTP & HTTPS [ 3 ] d. WiFi (802.11) [ 1 ] e. Ethernet [ 2 ] f. FTP [ 2 ] g. SMTP [ 2 ] 2. State which protocol would be used in the following scenarios : a. Transferring a music file to a friend over the internet. [ 1 ] b. Sending an email to a family member in America. [ 1 ] c. Using a wireless connection to play a mobile game. [ 1 ] d. Using a webpage to enter a password securely. [ 1 ] e. Watching a video on YouTube. [1 ] 3.4 Network Hardware & Routing Theory Topics 3.6 - 7 Layer OSI Model

Test your understanding of for loops and while loops in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python - Section 6 Practice Tasks Task One: Odd Numbers Use a for loop to print all odd numbers between 50 and 70 . You will need to use three values in the range brackets, including a step . Requirements for full marks: A comment at the start to explain what a for loop is. Use just two lines of code. Example solution: 51 53 55 57 59 61 63 65 67 69 Task Two: Fish Rhyme Use two separate for loops and some additional print lines to output this nursery rhyme: "1, 2, 3, 4, 5, Once I caught a fish alive, 6, 7, 8, 9, 10 then I let it go again" in the format shown . Requirements for full marks: Two for loops and two additional print lines (6 lines total). Example solution: 1 2 3 4 5 Once I caught a fish alive. 6 7 8 9 10 Then I let it go again. Task Three: Username & Password Create a program using a while loop that keeps asking a user to enter a username and a password until they are both correct . It may be easier to use a while True loop . You will need to use the and command in an if statement within the loop. Requirements for full marks: A comment at the start to explain what a while loop is. Example solution: Enter username: Ben43 Enter password: hamster Incorrect, please try again. Enter username: Ben44 Enter password: ben123 Incorrect, please try again. Enter username: Ben43 Enter password: ben123 Correct Correct login. Welcome Ben43 Task Four: Colour or Number Use a while True loop to let the user enter either A , B or C . A lets them guess a secret colour . B lets them guess a secret number . C breaks the loop , ending the program. Example solution: Enter A to guess a colour, B to guess a number, C to quit: A Guess the colour: green Incorrect! Enter A to guess a colour, B to guess a number, C to quit: A Guess the colour: pink Correct! Enter A to guess a colour, B to guess a number, C to quit: B Guess the number: 4 Incorrect! Enter A to guess a colour, B to guess a number, C to quit: C Quitting program... ⬅ 6b - W hile Loops 7a - Procedures ➡

Learn about different types of utility software including anti-virus, firewall and defragmentation. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 5.2: Utility Software Exam Board: OCR Specification: J277 Watch on YouTube : Utility Software What is utility software? Utility software are dedicated programs used for the maintenance and organisation of a computer system (this is known an 'housekeeping '). Utilities are required to run additional tasks not performed by the operating system . Anti-malware (such as an anti-virus or anti-spyware ), firewall and encryption software are examples of utilities and have been explained in section 4.2 . Data Compression is another utility that has been explained in section 2.5 . Other utility software include backup software , disk checkers , disk formatters and auto-updaters . Defragmentation What is fragmentation and how does it happen? Over time files stored on a hard disk drive may become fragmented - this is when the file is split into parts that are saved in different storage locations . Fragmentation occurs when there is limited contiguous space in which to store a file . This may happen as data is stored and then later deleted on the hard drive . New files are created which may be bigger than the spaces left by the deleted files . The new files are then split up . Fragmentation increases access time - files that are fragmented take longer to load and read because of the distance between the fragments of the file. How does defragmentation work? Empty spaces are collected together on the hard disk drive and file fragments are moved to be stored together. This means that fewer disc accesses are needed (requiring less physical movement ) as file fragments can be read consecutively . What are the effects of defragmentation? A defragmented file takes less time to read and access because the data is stored contiguously . The read/write head of the hard drive does not need to move as far to read the next piece of data because it is in the adjacent memory location , saving time . It also quicker to save new files because there is more free space together so it does not need to split the file and can store the data contiguously . Q uesto's Q uestions 5.2 - Utility Software: 1. Explain what fragmentation is and how a file may become fragmented . [ 3 ] 2. Describe the process of defragmentation . [ 3 ] 3. Explain the effects of defragmenting a hard disk drive. [ 3 ] 5.1 - Operating Systems Theory Topics 6.1a - Impacts of Technology

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 different categories of computer systems that can be used to access information including handheld, fixed and shared devices. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification for Unit 2 (Global Information). 1.3 - Access & Storage Devices Exam Board: OCR Specification: 2016 - Unit 2 Handheld Devices Examples of handheld devices: Handheld devices are small, light and possibly can be worn on the human body. These devices are very portable and easy to transport but their small size restricts the space for a powerful processor or high memory capacity. Handheld devices are becoming more powerful over time with extra features, storage options and network connectivity. Advantages: Light and portable so they can be easily carried on a person or in a pocket . Runs on battery power so do not need to be plugged into a power source (unless to charge) allowing for freedom of movement . Disadvantages: Low processing power due to small size and no cooling system . Relies on battery power which may not last for long. More likely to be lost, damaged or stolen . Generally small memory / storage capacity and low versatility . Smartphone Small Tablet eReader Smartwatch Portable Devices Examples of portable devices: Portable devices are larger and more powerful than handheld devices and can be carried easily in a bag. Laptops and larger tablets are the main examples of portable devices. Advantages: Light and portable so they can be easily transported in a laptop bag or small rucksack. Runs on battery power so they can work without a power outlet , such as to complete work on a train or in a library. More powerful and versatile than handheld devices. Disadvantages: Lower processing power and smaller memory / storage capacity than fixed devices like desktops. Reliant on their battery power which may only be a few hours. Laptop Large Tablet Fixed Devices Examples of fixed devices: Fixed devices are bulky devices that require a constant power connection . The most common example of a fixed device is a desktop computer which has a higher processing power and storage capacity than handheld and portable devices. Advantages: Desktop computers have the highest processing power of commercially available home / work computers and contain sufficient cooling systems to maintain temperature. Desktops and games consoles have large storage capacities and can be upgraded / expanded to even larger sizes. Desktop computers are very versatile and are powerful enough to be used for thousands of different purposes, from basic word processing and web browsing to server roles and data mining. Disadvantages: Reliant on a power outlet and cannot be transported whilst on. Heavy and difficult to move . May require additional components like a monitor. Typically more expensive than handheld and portable devices. Desktop Games Console Smart TV Shared Devices A shared device allows multiple users to access data at the same time . Cloud storage is the most common example of a shared device and is used by individuals, schools and businesses around the world through services such as Google Drive, Apple's iCloud and Microsoft's One Drive. A data centre is a dedicated building that contains computer systems - Facebook uses data centres across the globe so that their social media service can be available to users every second of the day. Database servers were explained in Unit 1 section 3.1 . Advantages: A ccessible by multiple users at the same time . For example, the database server can be accessed by employees of a bank simultaneously. Data centres allow online services to run all hours of the day and year . For example, Google uses data centres across the world to ensure their services can be accessed all of the time. Cloud storage frees up physical space for users as the storage is located (usually) on third-party servers. Cloud storage devices allow authorised users such as clients or staff members to access information or work remotely (outside of the office). Disadvantages: Shared devices are reliant on stable network connections . If a connection is lost, access to the device will be affected . Setting up shared devices within an organisation requires technical knowledge , especially for companies establishing their own cloud storage or data centre. Examples of shared devices: Cloud Storage Data Centre Database Server Q uesto's Q uestions 1.3 - Access & Storage Devices: 1. Identify the type of device that the following devices fit into: a. Laptop b. Cloud storage c. Desktop computer d. Smartphone [4 ] 2. Describe the advantages and disadvantages of using each of the 4 types of storage devices. a. Handheld devices [6 ] b. Portable devices [6 ] c. Fixed devices [6 ] d. Shared devices [6 ] 3. For the following scenarios explain which specific device (not type) which would be suitable. You must also justify your choice . a. Working on a spreadsheet on a train before work. [4 ] b. Taking a video of a penalty in a football match to upload to Twitter. [4 ] c. Working on a file with team members located across the country. [4 ] d. Playing Civilization VI on highest settings whilst listening to rock climbing podcasts in a separate tab. [4 ] 1.2 - Storage Media Topic List 1.4 - Internet Connections

Learn how pseudocode and flowcharts are written as part of algorithms. This content is based on the 2016 Eduqas / WJEC GCSE Computer Science specification. Algorithms Pseudocode 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 real 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 flowchart A flowchart can be used to visually represent an algorithm. The flowchart symbols are: Algorithm Example example Pseudocode {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 Stop Flowchart

Learn about how information can be classified into groups including private, public, sensitive and confidential. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification for Unit 2 (Global Information). 2.2 - Information Classification Exam Board: OCR Specification: 2016 - Unit 2 Information can be classified into different groups . Some data may fall into more than one classification. Sensitive Information Description: Information that should be protected from being publicly released as it could harm the safety or privacy of an organisation or an individual . Examples: Medical data that could be embarrassing to an individual if released. Financial data that will negatively impact the company if made public to competitors. Non-Sensitive Information Description: Information that can be released publicly with no fear of negative consequence . Examples: Store information including shop addresses , opening hours and the names of senior managers. Product information including prices , online reviews and general availability . Private Information Description: Private information relates to an individual and it should not be shared with anyone else without the data subject's permission . Private information is protected by the Data Protection Act and would need to be stored securely so it cannot be accessed without authorisation. Examples: Home addresses, contact information, birth dates and banking details . Employee data such as linked bank accounts and addresses. Public Information Description: Released to the public and can therefore be seen by anyone . Public information is non-sensitive . Examples: Social media usernames, posts and shared images. Public business information including addresses, promotional material and opening times. A government report like the national census every ten years. Personal Information Description: Identifiable data about a specific individual . Examples: Full name , date of birth , gender , marital status, medical history, sexual orientation and voting history. Business Information Description: Any kind of data about a specific business. This information could be public or private. Examples: Address of its headquarters Financial data or employee details. Annual sales figures . Confidential Information Description: Private data that is more restricted than sensitive information , with access limited to only those who need to know. Examples: Doctor / therapist notes Business Profits and losses Trade secrets Classified Information Description: Highly sensitive information stored by a government institution , requiring the highest levels of restricted access . Access is usually restricted by law and only viewable by authorised individuals or groups. In the UK there are three levels of classified information: OFFICIAL , SECRET and TOP SECRET . Examples: Military data Terrorism precautions Crime scene reports Anonymised Information Description: Anonymisation removes personally identifiable data from information so that an individual cannot be identified . This allows the information to be used in much wider context without running the risk of legal action. Examples: Partially anonymised information - where some of the personal information has been removed and replaced by a symbol . Completely anonymised information - where all identifiable data has been removed . Bank details are often partially or completely anonymised. A partially anonymised credit card number might be listed as: **** - **** - **** - 7427 Problems with anonymising data include: If sensitive data is not anonymised enough and the person can be identified . Useful information could be lost if too much data is anonymised . The public could lose trust in an organisation if data is insufficiently anonymised . Q uesto's Q uestions 2.2 - Information Classification: 1. Describe each type of information classification and give at least two examples : a. Sensitive information [3 ] b. Non-Sensitive information [3 ] c. Private information [3 ] d. Public information [3 ] e. Business information [3 ] f. Confidential information [3 ] g. Classified information [3 ] h. Anonymised information (partial and complete) [6 ] 2. State which classification(s) the following pieces of information would be categorised as. It might fit into more than one category. a. Shop opening times [1 ] b. Medical history [1 ] c. Twitter username [1 ] d. Crime scene report [1 ] 3. Describe three problems that organisations should consider when anonymising data . [6 ] 2.1 - Information Styles Topic List 2.3 - Quality of Information

Learn about troubleshooting tests and information to record when a hardware error occurs. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification. 1.6 - Hardware Troubleshooting Exam Board: OCR Specification: 2016 - Unit 1 What is troubleshooting? Troubleshooting means to analyse and solve a problem with a computer system. Hardware troubleshooting refers to fixing an issue with the physical parts of the computer or any connected devices. Hardware issues might occur as a result of damage (intentional or accidental), power surges or malware . Steps to Take When an Error Occurs Try to identify the problem by looking for the simplest explanation first (e.g. checking the power supply) and ask the user questions about the issue. Create a theory about what the cause of the problem could be and prepare to test the theory using a series of troubleshooting tests . Create a troubleshooting plan and record the steps that are taken before moving on to the next test. Check the system works after each stage of the plan. Create a findings document that explains if and how the problem was fixed, for future reference if the problem occurs again. Documentation Technicians and help desk (see 3.5 ) staff should document , on a fault sheet , the following information regarding the issue: The fault itself (such as 'system not turning on'). The system in question. The user logged in at the time. Exact date & time the problem occurred. Symptoms of the issue (such as 'slow load times' or 'beeping'). Problem history - checking if it has happened to this system before. Back up documentation - Whether the data been backed up recently. Troubleshooting Tools The following tools can be used to identify an error so a technician has a greater understanding of the problem. Event Viewer Event Viewer is a type of utility software that lists detailed information about an error when one occurs. It can be used to work out how to fix the issue and will display both minor and major faults. Power On Self Test (POST) On start-up, a power on self test (POST) checks memory, power, hardware and cooling systems are all working properly. Beep codes signal if an error has been detected; 1 beep will sound for no error but if multiple beeps are heard then an error has been discovered. Ping Test This is a connectivity test between two computers. A message is sent to the destination computer and waits for a return message named the echo reply . This procedure can be repeated with other systems until the source of the problem is identified from a computer that does not reply . Q uesto's Q uestions 1.6 - Hardware Troubleshooting: 1. Summarise the 'Steps to Take when an Error Occurs ' section into your own top three tips for what to do when a hardware error happens . [3 ] 2. List 6 pieces of information that an IT technician should record when a hardware error has occurred . [6 ] 3. Briefly explain the purpose of three troubleshooting tools . [6 ] 1.5 - Communication Hardware 1.7 - Units of Measurement Topic List

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 network devices such as a switch, router, modem and NIC. Also learn about internet terms and services including DNS and the Cloud. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 3.1b: Network Hardware + The Internet Exam Board: OCR Specification: J277 Watch on YouTube : The Internet Network Hardware DNS Servers The Cloud Network Devices When sending data across a network, files are broken down into smaller parts called data packets . Whole files are too large to transfer as one unit so data packets allow data to be transferred across a network quickly . Each packet of data is redirected by routers across networks until it arrives at its destination. Data packets may split up and use alternative routes to reach the destination address. When all the packets have arrived at the destination address the data is reassembled back into the original file. Wireless Access Point A Wireless Access Point provides a link between wireless and wired networks . It creates a wireless local area network that allows WiFi-enabled devices to connect to a wired network. Examples of a wireless access point in a public space could be a WiFi or Bluetooth hotspot , for example a WiFi hotspot in a coffee shop or airport to provide access to the internet. A wireless access point may be a separate device or built into another device such as a router. Router Routers are used to transfer data packets between networks . Routers receive data packets and use the IP address in the packet header to determine the best route to transmit the data. Data is transferred from router to router across the internet towards the destination. A router stores the IP address of each computer connected to it on the network and uses a list called a routing table to calculate the quickest and shortest route to transfer data. Switch A switch is used to connect devices together on a LAN . It receives data packets from a connected node, reads the destination address in the packet header and forwards the data directly to its destination. A switch will generate a list of the MAC addresses of all devices connected to it when it receives data , and must scan for a matching destination address before sending. An alternative to a switch is a hub but a hub is slower and less secure as it forwards a copy of received data to all connected nodes . Network Interface Controller / Card A Network Interface Controller (NIC ) commonly also known as a Network Interface Card is an internal piece of hardware that is required for the computer to connect to a network . The card includes a MAC address which is used when sending data across a LAN . An ethernet cable is plugged into the network card to allow data to be exchanged between the device and a network. A NIC used to be a separate expansion card but is now typically embedded on the motherboar d . Transmission Media Although not technically a device, the communication channel along which data is transferred will affect performance . Three common types of transmission media include: Ethernet cables - used typically on a LAN to transfer data between nodes and hardware such as switches. Examples include Cat5e and Cat6. Fibre Optic cables - very fast but more expensive and fragile cables typically used to send data quickly along a WAN . Data is sent as pulses of light . Coaxial cables - older , slower , copper cables that are not used as much in modern times as they can be affected by electromagnetic interference . The Internet The internet is a global network of interconnected networks . The world wide web (WWW ) is not the same as the internet. It is a way of accessing information , using protocols such as HTTPS to view web pages . Servers provide services on the internet , such as a web server which responds to the web browser (client) request to display a web page . The web server processes the client request to prepare the web page and return it so the web browser can display it to the user . A website must be hosted (stored) on a web server so that it can be accessed by others using the internet . A unique domain name (e.g. csnewbs.com) must be registered with a domain registrar – this is a company that checks the name is valid and not already taken . What is the Internet? DNS Servers A DNS ( Domain Name System ) server stores a list of domain names and a list of corresponding IP addresses where the website is stored. The first thing to understand is that every web page has a domain name that is easy for humans to remember and type in (such as www.csnewbs.com ) as well as a related IP address (such as 65.14.202.32) which is a unique address for the device that the web page is stored on. The steps taken to display a web page: 1. A domain name is typed into the address bar of a browser . 2. A query is sent to the local DNS server for the corresponding IP address of the domain name . www.facebook.com 3. The local DNS server will check if it holds an IP address corresponding to that domain name. If it does it passes the IP address to your browser . 66.220.144.0 4. The browser then connects to the IP address of the server and accesses the web site . If the local DNS server does not hold the IP address then the query is passed to another DNS server at a higher level until the IP address is resolved. If the IP address is found, the address is passed on to DNS servers lower in the hierarchy until it is passed to your local DNS server and then to your browser. Cloud Storage The cloud refers to networks of servers accessed on the internet . Cloud computing is an example of remote service provision . Cloud servers can have different purposes such as running applications , remote processing and storing data . When you store data in 'the cloud', using services such as Google Drive or Dropbox, your data is stored on large servers owned by the hosting company . The hosting company (such as Google) is responsible for keeping the servers running and making your data accessible on the internet . Cloud storage is very convenient as it allows people to work on a file at the same time and it can be accessed from different devices. However, if the internet connection fails , or the servers are attacked then the data could become inaccessible . Cloud Storage Characteristics: ✓ - Huge CAPACITY and you can upgrade your subscription if you need more storage. ✓ / X - Cloud storage is difficult to rank in terms of PORTABILITY , DURABILITY and ACCESS SPEED because it depends on your internet connection. A fast connection would mean that cloud storage is very portable (can be accessed on a smartphone or tablet) but a poor connection would make access difficult . ✓ - Cloud storage is typically free for a certain amount of storage. Users can then buy a subscription to cover their needs - Dropbox allows 2 GB for free or 2 TB for £9.99 a month. Q uesto's Q uestions 3.1b - Network Hardware & Internet: 1a. Explain how a switch works. [ 2 ] 1b. Describe the purpose of a router . [ 2 ] 1c. State what WAP stands for and why it is used . [ 2 ] 1d. State what NIC stands for and why it is required . [ 2 ] 1e. State the differences between the three main types of transmission media . [ 3 ] 2a. State what the internet is and how it is different to the world wide web . [ 2 ] 2b. What is web hosting ? [ 2 ] 3a. What is a DNS server ? [ 2 ] 3b. Describe, using a mix of text and icons / images , how a DNS server is used to display a web page . [5 ] 3c. Describe how a DNS server searches for an IP address if it is not found on the local DNS server . [ 2 ] 4a. Describe what cloud computing is. [ 2 ] 4b. State two advantages and two disadvantages of the cloud . [ 4 ] 3.1a - Network Types & Performance Theory Topics 3.2a - Wired & Wireless Networks

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 6 'Guess the Word' Game Create a Python program similar to the hit New York Times puzzle game Wordle . Allow the user to make guesses to match the randomly chosen hidden word , stopping when they get it correct. You can download a list of 5-letter words on this page. You will need to read in each line of the list and randomly select one - don’t forget to import the random library . Check if each letter of the user’s inputted word is in the randomly selected word . If you are using an IDE like Replit you can use the colorama library and the Fore command to turn the text: Green if the letter is in the correct position . Red if the letter is not in the selected word . Yellow if the letter is in the selected word but not in the correct position . Add your own flair and additional features to your program as an extension, including limiting the number of guesses and recording how many attempts it took to get the correct answer. Download a file of 534 5-letter words: For this task, you will need to create a document and include the following sections (with screenshots where appropriate): An introduction to explain the Purpose of your program . A List of Requirements for a successful program. Screenshots of your code (with comments in your code to show understanding). Testing – Create a plan to show how you will test your program and then explanations of any errors that you found and how they were fixed . An Evaluation of what worked, what didn’t, and how you met each of your requirements from your original list. Also, discuss further improvements that you could have made to improve your program. Reminders for this task: You will need a while loop to repeatedly allows the user to enter words until they match the correct word. Section 10 will help you to open, write and r ead from files . Download the file of 5-letter words from the link above. You will need to randomly select a word from the file. The choice command will help. Selection will be necessary to check if each letter in the inputted word matches the letter in the same position in the correct word. String handling is needed to select specific letters in a string. You will need to use .rstrip() on the selected line (word) that you have randomly chosen from the file. This removes any hidden characters that may interfere with checking if it is equal to the inputted word. There are multiple ways to approach this program, and your solution might look different from the example. Break the problem down and focus on one part at a time. Example solution: The word the user enters should be checked , letter by letter , against the letters in the same position in the randomly chosen correct word . Remember that the first letter in a word has the position 0 , not 1. Below is an example of some incomplete code you may wish to use in your solution. ⬅ Extended Task 5 (Colour Collection) Extended Task 7 (Number Game) ➡

Learn about the eight roles of an operating system including CPU management, security, managing interrupts and the user interface. Based on the 2020 Eduqas (WJEC) GCSE specification. 6.1: Operating Systems Exam Board: Eduqas Specification: 2020 What is an Operating System? An operating system (OS ) is software that helps to manage the resources of a computer system . There are eight main roles of an operating system: Manage the CPU A critical role of the OS is to manage the CPU so that applications and processes can be run efficiently . The CPU is effectively managed by performing three further roles: Manage Memory (RAM) The OS reserves memory space in RAM for stored programs to be copied into. The FDE cycle is executed continuously to carry out the instructions. The OS also ensures that programs are appropriately managed so that data is stored in correct memory locations and not corrupted . Manage Interrupts A interrupt is an alert signal sent to the CPU when an application or hardware device requires immediate attention . The OS must efficiently manage interrupts so that a problem can be dealt with quickly if one occurs. Manage Multi-Tasking The OS manages tasks so instructions can be executed by the CPU in turn - this is called scheduling . The OS prevents processes from interfering with others and crashing. Tasks should appear to run simultaneously even though only one process can be executed at a time. Manage Backing Store The backing store is another term for secondary storage devices such as the magnetic hard disk drive , optical drives or solid state memory sticks. The OS ensures data is stored correctly and can be efficiently retrieved from the backing store. Files are organised in a hierarchical (logical) structure . Manage Peripherals A peripheral is an external device connected to a computer system to input or output data . The OS manages the receiving of data from input devices (such as a keyboard or mouse) and the transfer of data to output devices (such as a monitor or speaker). Manage Security The OS allows users to create, manage and delete accounts with different permissions. It also permits multiple users to log in and change passwords . Antivirus and firewall software is managed by the OS as well as some data encryption processes. Manage the User Interface The final function of an operating system is to provide a user interface , allowing a human to interact with the computer system . The way in which a user can navigate a computer system is known as human-computer interaction ( HCI ). Graphical User Interface (GUI) The most common type of user interface is a graphical user interface (GUI ) which can be presented in the following ways: Icons are displayed to represent shortcuts to applications and files. Multiple windows can be opened at the same time and switched between. A folder and file system is displayed and manipulated allowing for copying , searching , sorting and deleting data. The interface can be customised , such as changing font sizes and the desktop background . The taskbar allows shortcuts to be pinned for quick access . Menus can be opened from the Start button to display files and shortcuts. System settings can be accessed such as network and hardware options . Q uesto's Q uestions 6.1 - Operating Systems: 1. Describe each role of the operating system : 1. Manage the CPU [ 2 ] 2. Manage memory [ 2 ] 3. Manage interrupts [ 2 ] 4. Manage multi-tasking [ 2 ] 5. Manage backing store [ 2 ] 6. Manage peripherals [ 2 ] 7. Manage security [ 2 ] 8. Manage the user interface [ 2 ] 2. Describe 5 different ways the operating system can provide a graphical user interface (GUI) . [5 ] 3. Describe two advantages and two disadvantages of using the following types of human-computer interaction (HCI) : a. Command-Line interface [ 4 ] b. Touch-Sensitive interface [ 4 ] c. Menu-Driven interface [ 4 ] d. Voice-Driven interface [ 4 ] Command-Line Interface Other types of user interface do exist, such as a command-line interface (CLI ). This type of interface is entirely text-based and requires users to interact with the system by typing commands . This is a complicated process and mistakes could easily accidentally delete data. There are many commands to learn so only experts who have been trained t o learn this interface will be able to efficiently make use of it. Menu-Driven Interface A menu-driven interface displays data in a series of linked menus . Examples include cash machines (ATMs) and old iPods . This type of interface is generally user friendly and easy to use as commands do not need to be memorised. However it can be annoying to find specific data through a large number of menus without a search feature. Touch-Sensitive Interface Another type of user interface is a touch-sensitive interface , used with smartphones and tablets . A human interacts with the device by pressing on a touchscreen , making it very intuitive and suitable for most users without training. Touch-sensitive interfaces may not work with dirty or wet fingers and it will take longer to write text compared to using a keyboard. Voice-Driven Interface A voice-driven interface can be controlled by speaking commands aloud to a listening device. Examples include Amazon's Alexa devices, Apple's Siri technology and Google Home . This interface is intuitive , can be used hands-free and helps to speed up processes . However commands may be misheard or limited in what can be performed. 5.1 - Data Structures Theory Topics 6.2 - Utility Software