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The homepage for the HTML section on CSNewbs. Learn how to create an HTML website from scratch and how each tag works. I'm Arthur the Alligator and I'm here to teach you HTML. HTML GUide Show me how to make a webpage in HTML from scratch. List of Tags Show me a list of tags I can use.

Learn about the six parts of a data packet and how packet switching works. Based on the 2020 Eduqas (WJEC) GCSE specification. 3.2: Data Packets & Switching Exam Board: Eduqas / WJEC Specification: 2020 + What is a data packet? 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. Contents of a Data Packet Data packets contain six distinct pieces of data which are used to redirect the packets towards the destination address. Packet Switching vs. Circuit Switching The key difference is that a circuit-switched network sends data along the same route . A packet-switched network sends data packets along different routes . Packet Switching With a packet-switched network the data is split into packets . The data packets are transmitted over a network and may take different routes to its destination. When all the packets have arrived the data is reassembled . The Internet is an example of a packet-switching network. Advantages of Packet Switching: Transmission is more secure as it is harder for a hacker to intercept complete data because it can take different routes . If a network device fails the data packets can take an alternative route . Data packets can be sent efficiently and individually across less busy routes . Disadvantages of Packet Switching: Reassembling the data takes longer because packets may arrive out of order . It is less reliable than circuit switching as some data packets may not reach the destination (this is called packet loss ). Circuit Switching When data is transmitted over a circuit-switched network all of the data takes the same route to the destination address in one continuous stream . The data is quickly reassembled at the destination because it is already in the correct order . The old telephone system is an example of a circuit-switched network. Advantages of Circuit Switching: Reassembling the data is quick because the packets arrive in the order that they were sent. It is more reliable than packet-switching because data is sent in one continuous stream . The transmission is fast and should encounter fewer errors - once the connection has been securely established . Disadvantages of Circuit Switching: Less secure as hackers could intercept the data and more easily access the data as it all takes the same route. Establishing a connection takes time to set up. If any device fails on the route then the whole connection breaks and data transfer will be incomplete. Q uesto's Q uestions 3.2 - Data Packets & Switching: 1. Draw the data packet diagram and label all 6 pieces of information . [ 6 ] 2a. Describe how packet switching works . [3 ] 2b. Describe the advantages of packet switching . [3 ] 2c. Describe the disadvantages of packet switching . [2 ] 3a. Describe how circuit switching works . [3 ] 3b. Describe the advantages of circuit switching . [3 ] 3c. Describe the disadvantages of circuit switching . [3 ] 3.1 - Network Characteristics Theory Topics 3.3 - Network Topology

Learn about sorting algorithms - merge and bubble sort - and searching algorithms - linear and bubble search. Based on the 2020 Eduqas (WJEC) GCSE specification. 8.4: Sorting & Searching Algorithms Exam Board: Eduqas / WJEC Specification: 2020 + Merge Sort Merge sort is a sorting algorithm based on the idea of ‘divide and conquer ’. A merge sort divides a list into half , again and again until each data item is separate . Then the items are combined in the same way as they were divided , but now in the correct order . When the individual lists are all merged together as one list again, then the data is in order and the algorithm will end . Bubble Sort This algorithm is based on the comparison of adjacent data elements . Data elements are swapped if they are not in the correct order . A bubble sort is not suitable for large sets of data. Linear Search A linear search is the most simple search algorithm. Each data item is searched in order from the first value to the last as if they were all laid out in a line . The list does not have to be in any order before it is searched . This search is also known as a sequential search because the list is searched in a sequence from start to end. For large lists , this search is not very efficient . Binary Search A binary search is a much more efficient searching algorithm as it generally searches through fewer data and is often much quicker - especially for large data sets. In a binary search, the middle point of the data is selected with each iteration and many data items can be ignored. However, the list of data must already be sorted in order before a binary search can take place. Q uesto's Q uestions 8.3 - Searching & Sorting Algorithms: Linear Search Explain step-by-step how the number 8 would be found in the following list using a linear search : 12, 5, 3, 2, 8, 19, 14, 6 [4 ] Binary Search Explain step-by-step how the number 2 would be found in the following list using a binary search : 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 [6 ] Merge Sort Explain step-by-step how a merge sort would sort the following list of numbers: 4, 8, 5, 1, 3, 6, 7, 2 [6 ] Bubble Sort Explain step-by-step how a bubble sort would sort the following list of numbers: 3, 2, 6, 4, 1, 4 [6 ] Watch on YouTube Watch on YouTube Watch on YouTube Watch on YouTube 8.3 - Writing Algorithms Theory Topics 8.5 - Validation & Verification

Navigate between all Unit F160 (Fundamentals of Application Development) topics in the OCR Cambridge Advanced National in Computing (AAQ) specification. Qualification: Cambridge Advanced National in Computing (AAQ) Unit: F160: Fundamentals of Application Development Certificate: Computing: Application Development (H029 / H129) Unit F160: Fundamentals of Application Development These pages are based on content from the OCR Cambridge Advanced National in Computing (AAQ) specification . Unit F160 YouTube Playlist Topic 1: Types of Software 1.1 - Programs and Applications 1.2 - Operating Systems 1.3.1 - Application Types 1.3.2 - Application Software Categories 1.3.3 - Application Software Types Topic 2: Software Development Models 2.1 - Software Development Models 2.2 - Development Phases Topic 3: Planning Development Projects 3.1 - Planning Projects 3.2 - Project Planning Tools Topic 4: Application Design Scoping 4.1 - Gathering Client Requirements 4.2 - Client Requirement Specifications 4.3 - Decomposition Methods Topic 5: Human-Computer Interface 5.1.1 - Types of Human-Computer Interaction (HCI) 5.1.2 - Types of Devices 5.2 - HCI Visual Design Considerations 5.3 - HCI Design Documents & Diagrams Topic 6: Job Roles & Skills 6.1 - Job Roles 6.2 - Communication Skills

Learn about software development methodologies such as the waterfall lifecycle, agile methodologies, extreme programming, the spiral model and rapid application development (RAD). Based on the OCR H446 Computer Science A-Level specification. Exam Board: OCR A-Level 2.3 - Software Development Specification: Computer Science H446 Watch on YouTube : Waterfall Lifecycle Extreme Programming Spiral Model Rapid Application Development Software development models are step-by-step methods for creating and maintaining software . They are used to keep projects organised , reduce mistakes and make sure the finished program meets the user’s needs . Different models suit different types of projects . Waterfall Lifecycle The waterfall model is a linear and structured approach where each phase is completed one at a time in order . It needs all requirements to be clearly defined at the start , with little to no changes allowed once a phase is finished . This model is best suited for projects with fixed requirements and minimal risk of change . YouTube video uploading soon Extreme Programming Extreme Programming ( XP ) is a type of agile methodology that uses an iterative and flexible approach, progressing in small , usable chunks called iterations (or sprints ). It relies on frequent collaboration with stakeholders and user feedback to adapt to changing requirements . This model is ideal for dynamic projects where quick delivery and frequent updates are important. YouTube video uploading soon Spiral Model The spiral model combines iterative development and risk management , progressing through repeated cycles of planning , risk assessment , engineering ( development and testing ) and evaluation . Each loop focuses on identifying and addressing risks early in the project. It is ideal for complex and high-risk projects where requirements may change over time . YouTube video uploading soon Rapid Application Development The rapid application development ( RAD ) model focuses on quickly building software through iterative development and frequent user feedback . It uses reusable components , time-boxing and constant feedback to speed up the delivery of an effective final product . RAD is best suited for projects that need to be completed quickly and where requirements can evolve during development . YouTube video uploading soon This page is under active development. Check here for the latest progress update. Q uesto's K ey T erms Software Development: waterfall lifecycle, agile methodology, extreme programming (XP), spiral model, rapid application development (RAD) D id Y ou K now? Agile development is named after the ' Agile Manifesto ' - a set of principles for software development agreed by a group of developers at a ski resort in Utah , USA in 2001 . 2.2 - Applications Generation A-Level Topics 2.4 - Programming Languages

Learn how to create your own web page in HTML. The guide features 10 easy to follow steps from setting up the basic tags to adding images, videos and more pages. When you see the checklist icon, complete the task in order to make your own HTML web page. HTML Guide 1. Setting up the web page 2. Essential tags 3. Text tags 4. Hyperlinks 5. Images 6. Organisation tags 7. Head tags 8. Videos 9. Colours & Fonts 10. More pages Watch on YouTube: These steps will show you how to make a HTML fanpage so get thinking of an appropriate topic - maybe your favourite book, movie or sports team? Download Notepad++ at home

Learn about the differences between CISC and RISC processors, GPUs and multicore and parallel systems. Based on the OCR H446 Computer Science A-Level specification. Exam Board: OCR A-Level 1.2 - Types of Processor Specification: Computer Science H446 Watch on YouTube : CISC and RISC GPUs Multicore & parallel systems Instruction Sets An instruction set is the complete list of machine code instructions a CPU is designed to execute as part of the FDE cycle . CISC (Complex Instruction Set Computer ) CPUs have a large set of complex instructions , so tasks can be achieved in fewer lines of code , but some instructions take multiple clock cycles . RISC (Reduced Instruction Set Computer ) CPUs use a smaller set of simple instructions , each designed to execute in a single clock cycle , making execution faster but sometimes requiring more instructions overall . GPUs A GPU (Graphics Processing Unit ) is a co-processor with thousands of smaller cores designed for parallel processing . This is in contrast to the CPU , which has fewer but more powerful cores . GPUs are used for rendering images , animations and video for fast , realistic graphics in games and multimedia . Because of their ability to handle many calculations at once , GPUs are widely used for non-graphical purposes too, such as machine learning , scientific simulations , data analysis and cryptocurrency mining . Multicore & Parallel Systems A multicore processor has multiple independent cores on a single CPU chip . Each core can carry out its own FDE cycle , so tasks can be split up , enabling multitasking and faster processing . However, only software designed to use multiple cores will benefit from this increased performance . A parallel system uses multiple processors (or cores ) working together on the same problem at the same time . This may involve multiple cores within one CPU or multiple CPUs in a single machine . Parallel processing greatly improves performance for tasks that can be divided into smaller sub-tasks , such as simulations and graphics rendering . However, some problems cannot be parallelised because they must be executed sequentially . Q uesto's K ey T erms Instruction Sets: instruction set, complex instruction set computer (CISC) , reduced instruction set computer (RISC) GPUs: graphics processing unit (GPU) Multicore Systems: multicore systems, parallel processing D id Y ou K now? Sony coined the term ' GPU ' for the PlayStation (1994), making it one of the first home consoles with a dedicated graphics processor . The term was later popularised further by NVIDIA in 1999 with the GeForce 256 . 1.1 - The Processor A-Level Topics 1.3 - Input, Output & Storage

Learn how to use App Inventor 2 to create simple programs. Perfect for key Stage 3 students to experiment with block coding and objects What is App Inventor? App Inventor 2 Link App Inventor 2 is software developed by Massachusetts Institute of Technology (MIT ), a research university in America. It allows users to create simple apps and learn about the way that they work in a fun manner. There is no need to learn how to program with text editors as everything is based around blocks, a bit like Scratch. To open App Inventor 2 (the current version of the program) click the button in the top right. You will need to log in with a Google account. There are two layouts to App Inventor, Designer and Blocks . You can switch between them with the bottoms in the top right corner. This guide will show you how to make seven simple programs and introduce you to programming concepts such as variables and properties . Download all App Inventor images you will need for the 7 tasks by clicking the camera icon. Note to Computer Science Teachers - The easiest way to test programs made using App Inventor 2 is using the emulator which should be pre-installed by the IT technician team at your school. See here for information on how to set it up. Also, Google accounts are required to access and use App Inventor 2. Viewer - This is a mock-up of what your app will look like. Components - Each component can be renamed or deleted here. Designer Layout Palette - Drag the component that you want to use in your app, into the centre. Properties - Edit the settings for each component. Media - Upload images and sound here before they can be used in your app. Blocks Layout Viewer - This is space for you to drag blocks to make things happen. Blocks - Drag the code block that you want to use into the centre. The blocks connect together like in Scratch. Warnings - Any errors with your code will be displayed here. Backpack - Drag code into to backpack to store it for later. KS3 Home Tasks 1 & 2

Learn about designing algorithms including constructing pseudocode and flowcharts. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). Exam Board: OCR 1.2: Designing Algorithms Specification: J277 Watch on YouTube : Inputs, Processes & Outputs Structure Diagrams Pseudocode Flowcharts Writing Code in Exams Trace Tables What is an algorithm? An algorithm is a set of instructions , presented in a logical sequence . In an exam you may be asked to read and understand an algorithm that has been written. To prove your understanding you may be asked to respond by actions such as listing the outputs of the algorithm, correcting errors or identifying an error within it. Programmers create algorithm designs as a method of planning a program before writing any code. This helps them to consider the potential problems of the program and makes it easier to start creating source code. There are two main methods of defining algorithms are pseudocode and flowcharts . In exams , OCR will display algorithms in their own 'OCR Exam Reference Language '. Visit the Python section of CSNewbs ---> OCR Exam Reference Language Below is a list of all of the code concepts from the OCR J277 GCSE specification that you need to know , presented in OCR Exam Reference Language (OCR ERL ), which is how code will be presented in the paper two exam . The code below is NOT Python . There are several differences between OCR ERL and real high-level languages like Python or Java , especially in the 'String Handling ' section and with for loops . In an exam, you can write in OCR ERL or a programming language you have learnt. All code-related videos in the CSNewbs YouTube series for Paper 2 show both OCR ERL and Python side-by-side . Basic Commands Annotation // Comments are written using two slashes Assignment name = "Harold" age = 49 Constants and Global Variables constant tax = 15 global name = "Admin" Input / Output name = input ( "Enter your name") print ("Transaction Complete") Casting str (29) int ("102") float (30) bool ("False") Random Number number = random (1,100) Selection Selection (if - then - else) if firstname == "Steven" then print("Hello" + firstname) elif firstname == "Steve" then print("Please use full name") else print("Who are you?") end if Selection (case select) switch day: case “Sat”: print(“It is Saturday”) case “Sun”: print(“It is Sunday”) default : print(“It is a Weekday”) endswitch Iteration Iteration (for loop) for i = 1 to 10 step 1 input item next i Iteration (while loop) while firstname ! = "Steven" firstname = input("Try again:") endwhile Iteration (do while loop) do firstname = input("Guess name:") until firstname == "Steven" String Handling Length of a String word = "dictionary" print(word.length ) outputs 10 Substrings word = "dinosaurs" print(word.substring (2,3)) outputs nos print(word.left (3)) outputs din print(word.right (4)) outputs aurs Concatenation name = "Penelope" surname = "Sunflower" print(name + surname) String Cases phrase = "The Cat Sat On The Mat" print(phrase .lower ) print(phrase .upper ) ASCII Conversion ASC ("C") returns 67 CHR (100) r eturns "d" File Handling File Handling - Reading Lines file1 = open ("Customers.txt") while NOT file1.endOfFile() print(file1.readLine() ) endwhile file1.close() File Handling - Writing to a (New) File newFile ("paint.txt") file2 = open ("paint.txt") paint = input("Enter a paint colour:") file.writeLine (paint) file2.close() Arrays Declare Array array names[3] array names = "Ella", "Sam", "Ali" Declare 2D Array array grid[4,5] Assign Values names[2] = "Samantha" grid[1,3] = "X" More Programming Keywords Connecting strings together using the + symbol is called concatenation . Extracting certain parts of a string (e.g. using .substring() ) is called slicing . An if statement within an if statement or a loop within a loop is called nesting . Flowcharts A flowchart can be used to visually represent an algorithm. It is more likely you will need to be able to interpret a flowchart rather than draw one. The flowchart symbols are: The terminator symbol is also known as a terminal . Algorithm Examples Below are two different methods for representing the same algorithm - a program to encourage people to buy items cheaply at a supermarket. The program allows the price of items in a supermarket to be entered until the total reaches 100. The total price and the number of items entered are tracked as the program loops. Once the total reaches 100 or more, an if statement checks how many items have been entered and a different message is printed if there are 20 or more items, 30 or more items or less than 20 items. Pseudocode // This is a program to see how many items you can buy in a supermarket before you spend over £100} total = 0 itemsentered = 0 while total < 100 itemprice = input ("enter the price of the next item") total = total + itemprice itemsentered = itemsentered + 1 endwhile if itemsentered >= 20 then print ("You are on your way to saving money.") elif itemsentered => 30 then print ("You're a real money saver.") else print ("Look for better deals next time.") endif Flowchart Reading Algorithms In an exam you may be asked to read an algorithm and prove your understanding , most commonly by listing the outputs . Start from the first line and follow the program line by line , recording the value of variables as you go . When you encounter a for loop , repeat the indented code as many times as stated in the range . Example Algorithm: procedure NewProgram() maxvalue = input() for i = 1 to maxvalue output (i * i) ??????? print("program finished") endprocedure Example Questions: 1. List the outputs produced by the algorithm if the 'maxvalue' input is 5 . 2. State the code that has been replaced by '???????' and what the code's purpose is. Example Answers: 1. Outputs: 1 4 9 16 25 program finished 2. Missing Code: next i Purpose: Moves the loop to the next iteration. Watch on YouTube Structure Diagrams Structure diagrams display the organisation (structure ) of a problem in a visual format , showing the subsections to a problem and how they link to other subsections . The noughts and crosses structure diagram below has subsections in light yellow. Each subsection could be coded by a different person . Structure diagrams are different to flowcharts (those show how data is input, processed and output within a program or system). You may be asked in an exam to draw or fill in a simple structure diagram . Trace Tables Trace tables are used to track the value of variables as a program is run . They can be used to manually track the values in order to investigate why the program isn't working as intended . Each row in the trace table represents another iteration . Each column stores the value of a variable as it changes. See below how the trace table is updated for the simple algorithm on the left. num1 = 2 num2 = 5 for i = 1 to 3 output (num1 + num2) num2 = num2 - 1 next i print("complete") For most algorithms, not every variable will be updated in each iteration . Values may not be entered in the order of the trace table either. For example, each iteration outputs num1 + num2 and then decreases the value of num2 by 1. Q uesto's Q uestions 1.2 - Designing Algorithms: 1. What is the definition of an algorithm ? Name two ways an algorithm can be designed . [ 3 ] 2. Using a high-level programming language such as Python , or the OCR Exam Reference Language , write an algorithm that inputs 6 decimal numbers and outputs the total , largest , smallest and average values. [ 8 ] For example, entering 3.1 , 5.3 , 2.3 , 5.4 , 2.9 and 4.4 would output 23.3 (total), 5.4 (largest), 2.3 (smallest) and 3.9 (average). 3. Draw and label the flowchart symbols . [ 6 ] 4. What is the purpose of a structure diagram ? [ 2 ] 5. Create a trace table for the NewProgram() algorithm in the Reading Algorithms section on this page. [ 7 ] 1.1 - Computational Thinking Theory Topics 1.3 - Searching & Sorting

Test your understanding of selection (if statements) and operators (mathematical and logical). Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python - Section 4 Practice Tasks Task One: Spanish Numbers Create a very simple Spanish translation program. Let the user enter a number between one and four then print the Spanish word for that number using if , three elif s and else . One in Spanish is uno , two is dos , three is tres and four is cuatro . If they enter anything else print “I only know 1 to 4 in Spanish!” . Example solutions: Enter a number between 1 and 4: 3 tres Enter a number between 1 and 4: 5 I only know 1 to 4 in Spanish! Task Two: School Trip A school is organising a trip to Alton Towers . The coaches they are hiring can fit 45 people . Enter the total number of people going on the trip and work out how many coaches will be full (using integer division ) and how many people will be left over on a partly full coach (using modulo division ). Example solutions: How many people are going on the trip? 100 There will be 2 full coaches and 10 people on another coach. How many people are going on the trip? 212 There will be 4 full coaches and 32 people on another coach. Task Three: Driving Tractors There are different rules in the United Kingdom for what farmers at certain ages can drive . Ask the user to input their age and then output the relevant information below: Children under 13 cannot drive any tractors. A trained and supervised 13 to 15 year old can drive a low-powered tractor on private flat grass. 16 year olds with a provisional category F licence can drive tractors less than 2.45 metres wide. Young adults from 17 to 20 with the correct licence and training c an drive tracked vehicles that weigh less than 3,500kg. Adults over 21 years old , with the correct licence and training, can drive all types of tractor. Note: Always be safe around machinery in farms regardless of your age. Driving without adequate training and a licence is illegal. Example solutions: How old are you? 8 You cannot drive any type of tractor. How old are you? 13 If you are trained and supervised you can drive a low-powered tractor on private flat grass. How old are you? 19 With the correct licence and training you can drive tracked vehicles that weigh less than 3,500kg. Task Four: Avoid the Three Choose a category like planets , people in your class or months of the year. Secretly choose three of them . Ask the user to enter a word in your category. If they enter one of the three that you chose, they lose . Example solutions: I have secretly selected three months you must avoid! Enter a month of the year: April AHA! You chose one of the secret months, you lose! I have secretly selected three months you must avoid! Enter a month of the year: December Well done, you didn't choose one of my three! ⬅ 4c - Logical Opera tors 5a - Random ➡

Learn about different types computers such a desktops, games consoles, laptops, smart speakers, smart TVs, smartphones, tablets, augmented reality (AR), virtual reality (VR) and mixed reality (MR) devices. 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) 5.1.2 - Types of Device Watch on YouTube : Types of Device Applications can be developed for a range of different devices , each type of device having its own characteristics and common uses . The characteristics of popular devices, such as laptop and tablets , may be well known, but ensure you know the difference between augmented reality ( AR ), virtual reality ( VR ) and mixed reality ( MR ) devices. Types of Device Common Devices Desktops are powerful and customisable personal computers designed for use at a desk . Game consoles are designed specifically for playing video games , usually connected to a TV . Laptops are portable computers with a built-in screen and keyboard , suitable for work on the go . Smart speakers are voice-controlled devices that play music , answer questions and can control smart home gadgets . Smart TVs have internet access , interactive features and apps for streaming and browsing . Smartphones have internet , GPS and Bluetooth connectivity , apps and communication functions . Tablets use a touchscreen larger than a phone, they are more portable than a laptop and good for browsing and media . Augmented Reality (AR ) is technology that overlays digital images or information onto the real world . Virtual Reality (VR ) uses a computer-generated 3D environment that fully immerses the user , usually with a headset . Mixed Reality (MR ) is a blend of AR and VR where digital objects interact with the real world in real time . Q uesto's Q uestions 5.1.2 - Types of Device: 1. Explain the difference between the three types of 'reality ' devices . [3 ] 2. Justify which devices a streaming service should consider for an app . [4 ] 3. Describe the characteristics of any devices not covered in your responses to Q1 and Q2 . [ 5 ] The AR app Pokémon Go was so popular when it released in 2016 that within the first 6 months players had walked a combined 8.7 billion kilometres ( 200,000 trips around the Earth ). D id Y ou K now? 5.1.1 - Human-Computer Inter. Topic List 5.2 - Visual Design Considerations

Learn how to use the style tags in an HTML document to edit the background colour and font text and colour. 9. Style (Colours & Fonts) HTML Guide Watch on YouTube: Before you add any colours or font styles, you need to add tags. The style tags must be written within your head of your HTML document! Add them below your title tags: Add the