Learn how to make simple calculations in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 3b - Simple Calculations Simple Calculations in Python You can perform calculations on numbers in Python using the four main operators : print ( 89 + 47) print ( 89 - 47) print ( 89 * 47) print ( 89 / 47) = 136 42 4183 1.8936170212765957 For addition , use the plus sign + To subtract numbers, use the dash symbol – (but not an underscore _ ) For multiplication , use an asterisk * which can be made by pressing Shift and 8 on a typical keyboard. To divide numbers, use a forward slash / (but not a backslash \ ) Use a string and the calculation to make the output user friendly . print ( "53 x 7 =" , 53 * 7) = 53 x 7 = 371 Simple Calculations Task 1 ( + - * /) Print four different simple calculations, using a different operator ( + - * / ) for each. Make the output user friendly by also showing the calculation (not just the answer). Copy the divide symbol here using Ctrl and C : ÷ Example solution: 18 + 35 = 53 18 - 35 = -17 18 x 35 = 630 18 ÷ 35 = 0.5142857142857142 Using Variables in Calculations You can also perform calculations on variables . The example below has the values of the variables pre-written. You need to store the result in a variable . The total variable has been used to store the result of the multiplication. num1 = 12 num2 = 20 total = num1 * num2 print ( "The total is" , total) = The total is 240 The example below allows the user to input values . num1 = int ( input ( "Enter number one: " )) num2 = int ( input ( "Enter number two: " )) total = num1 + num2 print ( "The to ta l is" , total) Enter number one: 21 Enter number two: 82 The total is 103 = Don't leave the user in the dark, better user interfaces are clear and explain what outputted values mean: num1 = int ( input ( "Enter number one: " )) num2 = int ( input ( "Enter number two: " )) answer = nu m1 - num2 print (num1 , "-" , n um2 , "=" , answer) Enter number one: 83 Enter number two: 29 83 - 29 = 54 = Simple Calculations Task 2 ( Divide by 3) Use an input line with int to ask the user to enter a number . Divide the number by 3 and output the result . Example solution: Enter a number: 11 11 divided by 3 is 3.6666666666666665 Simple Calculations Task 3 ( Add 3 Numbers ) Make three input lines using int to ask the user to enter three numbers . Add the numbers together and output the total . Example solution: Enter the first number: 45 Enter the second number: 32 Enter the third number: 19 The total is 96 ⬅ 3a - Data Types Section 3 Practice Tasks ➡

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 how sounds are represented in a computer system including how analogue sound waves are converted into binary. Also, learn about sample rate, bit depth and metadata. Based on the 2020 Eduqas (WJEC) GCSE specification. 4.7: Sound Representation Exam Board: Eduqas Specification: 2020 Converting Analog Sound to Binary To store sound on a computer analog sound waves must be converted in to digital data ( binary ). The sound is sampled using an ADC (Analog to Digital Convertor) and stored as a binary value (such as 01010011) called a sample . 0010 1011 0101 0101 Analog sound wave ADC (Analog to Digital Converter) Binary sample Sampling an Analog Sound Wave Digital sampling is discrete (separate) and not continuous like analog waves. To get the highest quality sound, many samples are taken to recreate the analog wave as closely as possible . Sample Rate The sample rate is the number of samples taken per second . It is measured in kilohertz (kHz), for example CD quality is 44.1kHz (44,100 samples per second). The higher the sample rate , the better the audio quality as the digital data more closely resembles an analog wave . However, higher sample rates result in larger file sizes because more data is stored for each individual sample. A low sample rate will result in a low-quality sound because the digital data does not closely resemble the original analog wave . A higher sample rate will result in a higher-quality sound because the digital data more closely resembles the original analog wave . Improving Audio Quality Bit Depth Bit Rate The bit rate is defined as the amount of audio data processed per second . It is measured in kilobytes per second (kbps ). The bit rate is calculated by multiplying the sample rate and bit depth . Because the bit rate is the measure of the sample rate and bit depth multiplied together, the higher the bit rate the higher the quality of the sound . The bit depth is the number of bits available to represent each sample . For example, a sample with a bit depth of 4 could be 0101 or 0111 or 1010. A sample with a bit depth of 8 could be 01010110 or 1010110 or 11001111. A common bit depth is 16 bits . The higher the bit depth , the more bits are available to be used for each sample. Therefore the quality is often higher as the wave more closely resembles an analog wave . The file size will also be larger if the bit depth is higher, as each sample stores additional bits . Example: A short audio sample has a bit depth of 4 and a sample rate of 10 samples per second . The clip is 15 seconds long . Calculate the bit rate by multiplying the sample rate and bit depth : 4 bits x 10 = 40 bits . Now that is the correct data for one second. Multiply the bit rate by the number of seconds in the file: 40 x 15 = 600 bits . To convert the answer from bits to bytes , divide by 8 . 600 bits ÷ 8 = 75 bytes . Calculating File Size Metadata for Sound Files Music libraries such as Apple Music or Spotify store a huge amount of metadata on each song. Metadata is additional data about a file such as: Artist Title / Track Title Product / Album Title Track Number Date Created / Year Genre Comments Copyright Software Type Duration File size Bit rate Sampling rate Channels Volume Q uesto's Q uestions 4.7 - Sound Representation: 1. Explain how an analog sound wave is converted into a binary sample . [ 2 ] 2a. What is a sample rate ? [1 ] 2b. Explain two ways an audio file will be affected if the sample rate is increased . [4 ] 3a. What is bit depth ? [2 ] 3b. Explain two ways an audio file will be affected if the bit depth is increased . [4 ] 3c. Explain what the bit rate is. [ 2 ] 4 . An audio sample has a bit depth of 8 , a sample rate of 10 and it is 12 seconds long . What is the file size in bytes ? [ 2 ] 5a. What is metadata ? [ 2 ] 5b. State four different types of metadata for audio files . [4 ] low bit rate = lower quality high bit rate = higher quality Converting Analog Sound to Binary 1 4.6 Graphical Representation Theory Topics 4.8 - Compression

Learn about algorithms including programming principles, variables and sequencing. Based on the 2020 Eduqas (WJEC) GCSE specification. 8.1: Programming Principles Exam Board: Eduqas Specification: 2020 Problem Solving There are four stages to computational thinking (smart problem solving ). Decomposition is when you break a problem down into smaller tasks so that it is easier to solve . Pattern Recognition is the process of identifying similar patterns within a problem . Abstraction is when you ignore unnecessary information and focus only on the important facts . Algorithms are the final stage as step-by-step rules are created to solve the problem . An algorithm is usually written as psuedocode or presented as a flowchart . Programming Constructs There are three constructs (ideas) of programming that most programs will contain: Sequence Structuring code into a logical, sequential order . Selection Decision making using if statements . Iteration Repeating code , often using for loops or while loops . Variables Large programs are often modular - split into subroutines with each subroutine having a dedicated purpose. Local variables are declared within a specific subroutine and can only be used within that subroutine . Global variables can be used at any point within the whole program . Local variable advantages Saves memory - only uses memory when that local variable is needed - global variables use memory whether they are used or not. Easier to debug local variables as they can only be changed within one subroutine. You can reuse subroutines with local variables in other programs. Global variable advantages Variables can be used anywhere in the whole program (and in multiple subroutines). Makes maintenance easier as they are only declared once. Can be used for constants - values that remain the same. Local & Global Variables Constants A variable is data that can change in value as a program is being run. A constant is data that does not change in value as the program is run - it is fixed and remains the same. An example of a constant in maths programs is pi - it will constantly remain at 3.14159 and never change. π π Counts & Rogue Values When using iteration (looping) the loop must eventually be able to stop. A count is a variable that is used to record the current iteration (loop number). A rogue value is an unexpected value that will cause the loop to end . For example by typing "Stop" into a loop that asks for numbers. Self-documenting Identifiers An efficient program will use variables with sensible names that immediately state their purpose in the program. Using variable names like 'TotalNum' and 'Profit' rather than 'num1' and 'num2' mean that other programmers will be able to work out the purpose of the code without the need for extensive comments. Q uesto's Q uestions 8.1 - Programming Principles: Problem Solving 1. What is meant by 'decomposition '? Why is it important ? [2 ] 2. What does the term 'abstraction ' mean? Why is it important ? [2 ] 3. What is pattern recognition ? [2 ] 4a. What is an algorithm ? [1 ] 4b. What are the two ways of writing an algorithm ? [2 ] Programming Constructs 1. Describe and draw a diagram for the 3 programming constructs . [6 ] Variables 1. What is the difference between local and global variables ? [4 ] 2. Describe two advantages of using local variables . [2 ] 3. Describe two advantages of using global variables . [2 ] 4. What is a constant ? Give an example . [2 ] 5. Why is it important to use self-documenting identifiers when programming? [2 ] 6. What is a count ? What is a rogue value ? [2 ] 7.1 - Language Levels Theory Topics 8.2 - Understanding Algorithms

Test your understanding of string and number handling techniques in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python - Section 9 Practice Tasks Task One It is the national hockey championships and you need to write the program for the TV channel showing the live games. Let the user enter the name of the first country that is playing. Then let the user enter the name of the second country . Shorten country 1 to the first two letters . Shorten country 2 to the first two letters . Bonus: Display the teams in uppercase . Example solution: Welcome to the National Hockey Championships!!! Enter the first country: Montenegro Enter the second country: Kazakhstan Scoreboard: MO vs KA G Task Two In some places, the letter G is seen as an offensive letter. The government want you to create a program to count how many times the letter G appears in a sentence . Let the user input any sentence that they like. You need to count how many g’s there are. Then print the number of g’s there are. Example solution: Enter your sentence: good day! great golly gosh, got a good feeling! There were 7 instances of that awful letter! Task Three A pet shop has just ordered in a batch of new dog collars with name tags. However, there was a mistake with the order and the tags are too small to display names longer than 6 characters . You need to create a program that checks the user’s dog name can fit. Let the user enter their dog’s name . Calculate the length of their name. Use an if statement to see if it is greater than 6 characters . If it is then print – Sorry but our dog tags are too small to fit that. Otherwise print – Excellent, we will make this dog tag for you. Example solutions: Welcome to 'Dogs and Cats' Pet Shop! What is the name of your dog? Miles Excellent, we will make this dog tag for you! Welcome to 'Dogs and Cats' Pet Shop! What is the name of your dog? Sebastian Sorry, our dog tags are too small! Task Four It’s literacy week and the Head of English would like you to create a vowel checker program to ensure that year 7s are using plenty of vowels in their work. Let the user enter any sentence they like. For each letter in the sentence that they have just entered you need to use if statements to check if it is a vowel . You will need to use the OR operator between each statement to separate them. After the for loop you need to print the number of vowels they have used. Example solution: Enter your sentence: Put that thing back where it came from, or so help me! You used 14 vowels in your sentence. Task Five Remember the national hockey championships? Well, the company that hired you just fired you… Never mind though, a rival scoreboard company want to hire you right away. You need to let the user enter two countries like last time. But this time you don’t want to calculate the first two letters, you want to print the last three letters . Example solution: Welcome back to the National Hockey Championships!!! Enter the first country: Montenegro Enter the second country: Kazakhstan Scoreboard: GRO vs TAN Task Six Too many people are using inappropriate names on Instagram so they have decided to scrap the username and will give you a code instead. The code is the 2nd and 3rd letters of your first name , your favourite colour and then the middle two numbers of the year you were born . Let the user input their name, then their favourite colour and then the year they were born. Using their data, calculate their new Instagram name! Example solution: Welcome to Instagram What is your name? Matthew What is your favourite colour? red Which year were you born in? 1987 Your new profile name is: ATRED98 Task Seven Copy the text on the right and create a program that will split the text at each full stop. Count the number of names in the list. Print the longest name. Example solution: The list contains 20 names The longest name is alexandria annabelle.clara.damien.sarah.chloe.jacques.mohammed.steven.rishi.raymond.freya.timothy.claire.steve.alexandria.alice.matthew.harriet.michael.taylor ⬅ 9b - Number Handling 10a - Open & Write To Files ➡

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 data units of storage from bit up to petabyte, as well as data capacity calculations. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 2.3: Data Units Exam Board: OCR Specification: J277 Watch on YouTube : Units of Data Storage Capacity Requirements All computer systems communicate , process and store data using binary . Binary is a number system consisting entirely of 0s and 1s . Why do computers use binary? Computer systems consist of billions of tiny transistors which are switches that only have two values - on (1 ) or off (0 ). Therefore all data must be represented and processed in this way. Everything that a computer needs to process must be converted into a binary format including text , images , videos and audio . 0010 1011 0101 0101 0110 0111 0101 0001 0101 0101 0101 0100 1010 1010 1010 1010 1111 1110 0010 1001 0100 1001 0010 0111 0111 0101 0011 1010 1000 0101 0110 0111 0000 1010 1010 0011 1101 1001 0010 1101 0010 0100 1001 0011 1010 1001 0101 0101 0010 0101 0111 0101 0101 1000 1011 0111 Units of Data Storage 0 / 1 All data in a computer system is made up of bits . A single bit is a 0 or a 1 . 4 bits (such as 0101 or 1101) is called a nibble . 1,000 bytes is called a kilobyte . A kilobyte can store a short email . A 8 bits is called a byte . A byte can store a single character . 1,000 kilobytes is called a megabyte . A megabyte can store about a minute of music . 1,000 megabytes is called a gigabyte . A gigabyte can store about 500 photos . 1,000 terabytes is called a petabyte . A petabyte can store about 1.5 million CDs . 1,000 gigabytes is called a terabyte . A terabyte can store about 500 hours of films . Calculating Data Capacity Requirements It is important to be able to calculate the required storage capacity for a given set of data . Example: A local DJ has a USB memory stick with a capacity of 32GB . There is currently only 9GB of space remaining . Each song is 6MB . How many songs can be stored on the remaining space of the USB stick? Solution: Because each song is recorded in megabytes but the USB stick capacity is measured in gigabytes , the values must be converted into the same storage unit . 9GB x 1000 = 9000MB 9000MB ÷ 6MB = 1,500 songs Q uesto's Q uestions 2.3 - Data Units: 1. Explain why computer systems use binary to represent data. [ 2 ] 2. Put the following data storage units in order from smallest to largest : a . kilobyte - gigabyte - byte - megabyte - nibble - bit [3 ] b. gigabyte - petabyte - kilobyte - byte - terabyte - megabyte [ 3 ] 3. A hard drive contains 25GB of remaining available storage space. Tim is an animator backing up video files. Each file is 200MB . How many files can he fit on the hard drive? [ 2 ] 4. Samantha is a musician. She has compressed each song to 900KB . Her USB memory stick contains 1.2GB of free storage. How many songs can she fit on the USB stick? [ 2 ] 5. A CD has a capacity of 650MB . How many 0.2GB audio files can be stored on the CD? [ 2 ] 0101 2.2 - Secondary Storage Theory Topics 2.4a - Number Systems

The Greenfoot homepage on CSNewbs with links to creating your own Greenfoot game from scratch, as well as key code and how to solve common errors. This section is aimed at the Eduqas GCSE 2016 specification. Links: Installing Greenfoot Greenfoot Game Tutorial Glossary of Key Code Help with Errors I'm Greta the Gecko and I'm here to teach you Greenfoot.

Learn about the purpose, characteristics, advantages, disadvantages, examples and client requirements of application software types, including off-the-shelf, custom off-the-shelf and bespoke software. Resources 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) 1.3.3 - Application Software Types Watch on YouTube : Off-the-Shelf Software Custom Off-the-Shelf Software Bespoke Software There are three application software types you need to know : Off-the-shelf software Custom off-the-shelf software Bespoke software For each software type , you need to know : Its purpose and common characteristics . The advantages and disadvantages of using the software. How client requirements affect the selection of that software. Application Software Types Off-the-Shelf Software Off-the-shelf software is pre-made and available for anyone to buy and use . It is designed for general users and common tasks . It is pre-developed and ready-made with standard features for a wide audience , not custom-built for a specific user. Its purpose is to provide a cost-effective , quick-to-deploy solution for popular applications . Custom Off-the-Shelf Software Custom off-the-shelf software is pre-built like regular off-the-shelf software , but can be slightly customised to meet specific user needs . It offers a balance between quick setup and limited personalisation . It supports configurable features such as add-ons , plugins or modules to extend or adapt functionality while the base software remains maintained and updated by the original developer . Bespoke Software Bespoke software is designed and built specifically for one organisation or user . It fits their exact needs but usually costs more and takes longer to develop . An example is a bespoke system developed for a specific bank with custom software to handle financial regulations , unique products and security needs . Other examples include government systems , hospital patient management and air traffic control . Q uesto's Q uestions 1.3.3 - Application Software Types: 1. Explain the differences in purpose and characteristics between off-the-shelf and custom off-the-shelf software. [4 ] 2. A dental surgery needs new software to manage its customer bookings . Justify which application software type they should use and why . [4 ] 3. Describe two advantages and two disadvantages of the three application software types on this page. [ 12 ] Off-the-shelf software gets its name from the days when software like Microsoft Word was sold on physical discs in shops , for customers to take off the shelf and install at home . D id Y ou K now? 1.3.2 - Software Categories Topic List 2.1 - Software Development Models

Learn about the wide range of style data and information can be presented in, both digitally and physically. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification for Unit 2 (Global Information). 2.1 - Information Styles Exam Board: OCR Specification: 2016 - Unit 2 There are many different ways that information can be styled and presented , both on-screen and physically . There are many more benefits and limitations to using each information style but some key ideas have been described below. T Text Text is a written (or typed ) format of information. ✓ Text provides detailed summaries and explanations . ✓ The format of text can be changed to suit its purpose (e.g. include bullet points or different colours). ✓ Text can be written in different languages so that all literate people can understand. X Large amounts of text can be difficult and time-consuming to read. It is generally less engaging than most other methods. X Text may include spelling errors or be factually incorrect . Graphics Graphics are a visual form of information. Examples include logos , photographs and diagrams . ✓ Graphics are multilingual - they can be understood by anybody regardless of their spoken language. Companies like IKEA will use the same graphics globall y . ✓ Graphics can present an idea or message immediately and can use associations (e.g. the colour red is associated with temperature or anger). ✓ Graphics are a more engaging method of presenting information than text. X Images may take longer to load over a data-restricted network, for example, images in an email may not be automatically downloaded. Video Videos are visual formats of information, often with audio . ✓ More engaging and easier to follow than reading large amounts of text. ✓ Videos can be used to convey a message in a short space of time , e.g. television adverts. ✓ Audio can be added to videos such as music for engagement or narration to explain a process. X Videos usually take up a relatively large amount of storage space , longer videos may take time to upload / download / transfer along a network. X Videos take a long time to create including filming, editing and narration. Animated Graphics Animated graphics are images with multiple frames , such as an animation of the heart showing individual steps that a user can pause and step through in their own time. ✓ Can be used to show a process and is easier to understand than reading text. ✓ Can be understood by all ages and language speakers . X Creating an animated graphic takes time to create , especially educational resources with multiple frames and annotation. 9 Numerical Numerical information is represented by numbers . This can include a wide array of different information including statistics, financial data, dates, ages and distances . ✓ Statistical data is easier to understand and manage in a numerical format than standard text - 234,567 is simpler to work with than "two hundred and thirty-four thousand, five hundred and sixty-seven". ✓ Numerical data can be exported into spreadsheets and presented as graphs to visualise the dat a . X Long numbers can be entered by humans incorrectly and lead to incorrect results . X Formatted data like telephone numbers cannot be stored as numerical because numerical does not allow spaces and does not allow the number to start with 0 . Audio Audio is an information type using sound waves. A common form of audio is music , such as the millions of tracks stored in music libraries like Spotify and YouTube. Non-music examples include spoken instructions and podcasts . ✓ Users can listen to information when they are otherwise busy and could not read, such as when walking or driving. ✓ Visually impaired users who are unable to read can still hear audio and interact with voice recognition software . ✓ Some users prefer listening to instructions rather than reading text . X Audio may not be suitable in some environments e.g. noisy areas . X Words may be misheard and misunderstandings made, possibly due to pronunciations or accents. Tactile Images Tactile images are a form of physical information that can be interpreted by touch . Specialist software is used to create raised lines on paper that people can experience by touching . Geographers can create 3D physical objects of environments such as valleys or volcanoes. This allows researchers and land surveyors to have a better understanding of a geographic area. ✓ Users can better understand a physical environment or prospective design if it is physically built. ✓ Visually-impaired users can feel the object instead of being able to see it. ✓ The tactile image can be used as a prototype for a target audience to feel and comment on. X It is difficult to share a tactile image without physically moving it, unlike digital or paper information styles. X Creating a tactile image requires specialist equipment like a 3D printer. *screams* Subtitles Subtitles are a textual form of information that can be shown along with visual data such as a video. Subtitles are written to transcribe audio , such as speech, into words . ✓ Hearing-impaired users can access audio information formats such as video by reading the subtitles. ✓ Subtitles can be used in noisy environments or when sound cannot be played. ✓ Subtitles can be used for translated speech , such as in promotional videos or television programmes. X Auto-generated subtitles are often incorrect . X Subtitles written by a human take a long time to type up and sync in time with the audio. Tables & Spreadsheets Tables and spreadsheets can store both numerical and textual data ready for analysis . Examples include simple database tables and financial spreadsheets of a company's profits this year. Microsoft Access is an example of database software that uses tables and Microsoft Excel is an example of spreadsheet software. When using spreadsheets (or databases) records can be locked ('record locking' ) so that only one person can make edits at any one time . Edits will be saved before unlocking the file. This will stop data being incorrectly overwritten and will ensure that the data in the spreadsheet is up-to-date , accurate and fit for purpose . Spreadsheets can be linked to other documents such as forms to directly import data from. This data can be ordered into different groups and conditional formatting can be used to automatically organise and style the data. Graphs and charts can be created using values stored in a spreadsheet to easily visualise the data . Modelling can be used to see the effect of variable changes (e.g. will raising the price of one product affect overall profit?). Database tables use queries (advanced searches) to find and display data based on given criteria (such as all males under 35). Mail merge can be used to automatically send emails to the customers highlighted in the query . A report can be generated from the query results to display the information in a structured format . This can be used to make decisions and analyse data . Boolean Boolean is a data type that can only have one of two specified values . These values are most commonly 'True' and 'False' or sometimes 'yes' and 'no'. Braille Braille is an example of a tactile image that can be physically touched . Braille characters represent letters or numbers that can be 'read' by touch - used primarily by those with visual impairments . Devices like braille terminals convert characters on a screen into braille, line-by-line so that blind people can understand the information through touch . A braille printer is used to output braille dots onto paper. ✓ Allows visually impaired users to interact with a computer system using a braille terminal . ✓ A braille printer can print documents written using braille to be given to blind people to 'read'. X Braille terminals can only display a limited amount of information at a time. X Braille is not used by many people except visually impaired people so few resources are written using braille. Charts & Graphs Charts and graphs can be used to present numerical data in a format that is easier to visualise and understand . They can be labelled to show different data values and they make it easier for viewers to identify trends and make comparisons between data. Large quantities of data, like census results, are easier to visualise in a graph than reading huge tables of numbers. ✓ Charts present numerical data in a format that is easier to visualise and understand . ✓ Charts and graphs can summarise information into one image data that would take paragraphs to explain in text. ✓ Displaying information in a graph allows users to easily identify trends and make comparisons between data . X Charts can be misleading or can display incorrect information if the numerical data is wrong. Q uesto's Q uestions 2.1 - Information Styles: 1. Describe the following information styles : a. Tactile Images [2 ] b. Braille [2 ] c. Boolean [2 ] 2. Describe two advantages and two disadvantages for each of the following information styles : a. Text [8 ] b. Graphics [8 ] c. Video [8 ] d. Animated Graphics [8 ] e. Numerical [8 ] f. Audio [8 ] g. Tactile Images [8 ] h. Subtitles [8 ] i. Braille [8 ] j. Charts & Graphs [8 ] 3a. Spreadsheets and database tables can be record locked . Explain what record locking is and why it is used . [4 ] 3b. Describe different ways that spreadsheets can be used. [6 ] 3c. Describe different ways that databases can be used. [6 ] 1.7 & 1.8 - Internet Pros & Cons 2.2 - Information Classification Topic List

Learn about malware such as viruses, worms, trojans, spyware, keyloggers and ransomware. Also, learn about phishing, data theft, interception and cyber attacks including SQL injection, IP address spoofing, DDoS attacks and brute force. Based on the 2020 Eduqas (WJEC) GCSE specification. 3.8: Cyber Threats Exam Board: Eduqas Specification: 2020 3.8a: Malware What is malware? Malware is any type of harmful program that seeks to damage or gain unauthorised access to your computer system. Virus A virus can replicate itself and spread from system to system by attaching itself to infected files . A virus is only activated when opened by a human . Once activated, a virus can change data or corrupt a system so that it stops working . Worm A worm can replicate itself and spread from system to system by finding weaknesses in software . A worm does not need an infected file or human interaction to spread. A worm can spread very quickly across a network once it has infiltrated it. Trojan A trojan is a harmful program that looks like legitimate software so users are tricked into installing it . A trojan secretly gives the attacker backdoor access to the system . Trojans do not self replicate or infect other files. Spyware Spyware secretly records the activities of a user on a computer. The main aim of spyware is to record usernames, passwords and credit card information . All recorded information is secretly passed back to the attacker to use. Keylogger A keylogger secretly records the key presses of a user on a computer. Data is stored or sent back to the attacker. The main aim of a keylogger is to record usernames, passwords and credit card information . Keyloggers can be downloaded or plugged into the USB port . Ransomware Ransomware locks files on a computer system using encryption so that a user can no longer access them. The attacker demands money from the victim to decrypt (unlock) the data . ? ? ? ? Attackers usually use digital currencies like bitcoin which makes it hard to trace them. 3.8b: Data Theft Phishing Phishing is the method of misleading individuals or organisations into sharing sensitive information (such as passwords or bank details ), often through the use of emails . Phishers may pose as a trusted company like Amazon or YouTube to direct users to open malicious attachments or encourage them to follow fraudulent links to steal their data . Social Engineering Social engineering means to trick others into revealing their personal data by posing as a trusted source . For example, impersonating an IT technician of a school via email and asking for a student's username and password . Interception This is when data packets on a network are intercepted by a third party (e.g. a hacker) and copied to a different location than the intended destination. Software called packet sniffers are used to intercept and analyse data packets. Physical Theft Computer systems (e.g. laptops) or storage devices (e.g. USB stick) may be stolen in public or from offices. Unwanted systems and storage media should be disposed of securely as data could be stolen from discarded information , such as old CDs or even printed paper. 3.8c: Online Threats & Attacks Hacking Hacking is the method of exploiting weaknesses in a system or network to create, view, modify or delete files without permission. A hacker is anyone who gains access to data or systems that they do not have authority to access. DoS Attack A DoS (Denial of Service ) attack is when a computer repeatedly sends requests to a server to overload the system . A server overload will slow the system and may take websites offline temporarily. A DDoS (Distributed Denial of Service ) attack is a coordinated attack using a botnet of infected systems to overload a server with requests . A botnet is a large group of devices controlled and used maliciously by an attacker. SQL Injection SQL ( Structured Query Language ) is a programming language used for manipulating data in databases . A SQL injection is when a malicious SQL query (command) is entered into a data input box on a website. If the website is insecure then the SQL query can trick the website into giving unauthorised access to the website’s database . An SQL injection can be used to view and edit the contents of a database or even gain administrator privileges . ' or 1 = 1 Brute Force Attack In order to break a password , every possible combination is tested in order from start to finish . This is not a quick method but it should break the password eventually and can be sped up if multiple computer systems are used at the same time. IP Address Spoofing An attacker changes the IP address of a legitimate host so any visitors to the URL are instead taken to a spoofed ( fake ) web page . This web page is used to record any inputted data (such as usernames and passwords) and send it back to the attacker . The spoofed web page can also be used to install malware . Q uesto's Q uestions 3.8 - Cyber Threats: 3.8a - Malware: 1. What is malware ? [ 2 ] 2a. Describe three characteristics of a virus . [3 ] 2b. Describe three characteristics of a worm . [3 ] 2c. What is a trojan ? [ 3 ] 2d. Describe how spyware and keyloggers work. [ 4 ] 2e. Explain how ransomware works and why it is difficult to trace attackers . [ 3 ] 2f. In your opinion, which malware do you think is the most dangerous and why ? [ 2 ] 3.8b - Data Theft: 1. Describe what is meant by ' phishing ' . [ 2 ] 2. Give an example of social engineering . [ 2 ] 3. What is interception ? What software is used to intercept data packets? [ 2 ] 4. Describe why systems and storage media should be disposed of securely . [ 1 ] 3.8c - Online Threats & Attacks: 1. Describe what is meant by ' hacking ' . [ 2 ] 2a. Describe what a DoS attack is and its impact . [2 ] 2b. Describe how a DDoS attack is different to a DoS attack . [2 ] 3. Describe what an SQL injection is and how an attacker would use it. [ 4 ] 4. Describe what is meant by a brute force attack . [ 2 ] 5. Describe IP address spoofing and its purpose . [ 3 ] 3.7 - The Internet Theory Topics 3.9 - Protection Against Threats

Learn about the methods of digital protection including antimalware, firewalls and obfuscation. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification for Unit 2 (Global Information). 6.6 - Logical Protection Exam Board: OCR Specification: 2016 - Unit 2 Logical protection refers to using digital methods of security to protect computer systems and data. Usernames & Passwords ****** Anti-Malware Usernames must be matched with a secure password to minimise the chances of unauthorised users accessing a system. Passwords should contain a mix of uppercase and lowercase letters , punctuation and numbers . Passwords should be of a substantial length (at least 8 characters) and should be regularly changed . Anti-virus software scans a system and removes viruses . If left to infect a system a virus could delete data or permit access to unauthorised users . Anti-spyware software removes spyware on an infected system so hackers cannot view personal data or monitor users. Organisations should install and regularly update anti-virus and anti-spyware programs. Firewall Encryption Firewalls prevent unauthorised access to or from a network . Firewalls filter data packets and block anything that is identified as harmful to the computer system or network. Firewalls can also be used to block access to specific websites and programs. A firewall can be in the form of a physical device which is connected to the network, or software installed on a computer system. Encryption is the conversion of data ( plaintext ) into an unreadable format ( ciphertext ) so it cannot be understood if intercepted . Encrypted data can only be understood by an authorised system with a decryption key . There are two types of encryption . Encryption at rest is when data is encrypted while it is being stored on a system or storage drive. Encryption in transit is to secure the data as it being transferred between systems on a network. Tiered Levels of Access Obfuscation ?????? The purpose of tiered levels of access is to grant different types of permission to certain users. Managing levels of file access ensures that only authorised people can access and change certain files . There are different levels of file access : No access Read-only - Allows a user to view but not edit. Read/write - Allows a user to view and edit. Obfuscation is when data is deliberately changed to be unreadable to humans but still understandable by computers . Program code might be obfuscated to stop rival programmers from viewing and stealing it if they were able to access it. Specialist software can be used to obfuscate data and convert it back into a human-readable format. Q uesto's Q uestions 6.6 - Logical Protection: 1a. Describe why usernames and strong passwords are necessary. [2 ] 1b. State 3 rules for choosing a strong password . [3 ] 2. Describe the purpose of anti-virus and anti-spyware software. [4 ] 3. Describe the roles of a firewall . [4 ] 4. Explain what encryption is. What are the two types? [4 ] 5. Why would an organisation use tiered levels of access ? What are the 3 levels of file access ? [5 ] 6. What is obfuscation ? State a scenario in which it would be used. [3 ] 6.5 - Physical Protection Topic List