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Learn how to start a new Greenfoot program and set up the world and actors ready for the next steps in creating a game. Part 1 of the Greenfoot Tutorial for the Eduqas/WJEC GCSE 2016 specification. 1. Setup & Populating the World Greenfoot Tutorial 1. Open Greenfoot This tutorial uses Version 2.4.2 which is the version students are given to use in the WJEC/Eduqas Component 2 exam . Click here for more information and how to download 2.4.2 . If you are using a more recent version the code should still work but the look of the program in the screenshots may be different. In the Component 2 exam of the 2016 WJEC/Eduqas specification you would skip ahead to the New Object Placements stage further down this page as the classes should be set up for you. Watch on YouTube: 2. New Scenario For a new project, click ' Scenario ' and then ' New '. If you are using a more recent version of Greenfoot select ' New Java Scenario '. Save this new project in a suitable location such as a folder named 'Greenfoot' . You may wish to save this project as ' SimpleGame ' or ' ExampleGame '. 3. Setup the MyWorld class The first thing to do is to create a subclass of World called MyWorld which becomes our background object. Right-click on the World class and select 'New subclass... ' Set the New class name to MyWorld . Choose any image from the 'backgrounds ' image category. I have chosen the 'cell.jpg ' image. Click the Compile button in the bottom right of the Greenfoot window to save the program . 4. Create the Main Character class Now to create a new class for the main character. Right-click on the Actor class and select 'New subclass... ' Give the new object an appropriate name and choose a relevant image . I have named my class 'Sheep ' and selected the sheep.png image. 5. Right-click on Actor and create two more classes: Collectable objects to pick up (e.g. my orange) An enemy character to avoid (e.g. my elephant) Don't forget to compile the program. Watch on YouTube: After creating your classes you must move them over to the game world. This is known as populating the world . 1. New Object Placements Right-click on your main character object and select the top option e.g. 'new Sheep()'. Drag your mouse to the world and click to drop it. Complete the following actions: Place 1 main character object. Place 5 collectible objects. Place 2 enemy objects. 2. Save the World Once you have populated your world with objects then right-click anywhere on the background and select 'Save the World '. This saves the positions of each object so that it won't reset every time you start a new game. You can close the MyWorld code that automatically opens when you save the world, we never add any code to this window. Part 2 - Movement (Arrow Keys) >

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 the importance of testing applications, test plan structure, test types and test data. Resources based on Unit F161 (Developing Application Software) for the OCR Cambridge Advanced Nationals in Computing (H029 / H129) AAQ (Alternative Academic Qualification). Qualification: Cambridge Advanced Nationals in Computing (AAQ) Certificate: Computing: Application Development (H029 / H129) Unit: F161: Developing Application Software 5.1 - Testing Watch on YouTube : Purpose of testing Test plan structure Test data Types of testing You need to know the purpose , importance , advantages and disadvantages of testing applications , as well as the impacts of not carrying out testing . You must understand the structure and contents of test plans and the importance of testing , remedial actions and retesting during application development. You need to know the role of each type of test data (normal , extreme and erroneous ). Finally, the purpose , advantages and disadvantages of each type of testing (technical and user ) must be known as well as when and how each type should take place . What You Need to Know Purpose of Testing ? YouTube video uploading soon Test Plan Structure ? YouTube video uploading soon Types of Test Data ? YouTube video uploading soon Types of Testing ? YouTube video uploading soon Q uesto's Q uestions 5.1 - Testing: 1. What? [2 ] 2. What? [1 ] 3. What? [1 ] 4. What? [1 ] ? D id Y ou K now? 4.1 - Security Considerations Topic List 5.2 - Application Installation

Learn how to create and use lists in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 8a - Using Lists Lists A list is a temporary data structure . Any changes made to the list while the program is running will not be saved the next time it is run . Data can be added to and removed from lists so they can change in size (unlike an array which is fixed and not used in Python). It is important to note that each data element in a list has an index so that it can be specifically referenced (to delete it for example) and that indexes start at 0 . A list of the rainbow colours in order would start at 0 like this: Creating & Printing Lists Lists use square brackets in Python. Separate list items with commas . Strings must use speech marks and integers do not use speech marks. people = [ "Alan" , "Jesse" , "Max" , "Jack" ] years = [ 2010, 2019, 2001, 2016 ] There are many different ways to print items from a list depending on how you want it to look . Print all items on one line Type the list name into a print command to output the complete list . Typing an asterisk * before the list name removes punctuation . cities = [ "Shanghai" , "Sao Paolo" , "Bishkek" , "Asmara" ] print (cities) cities = [ "Shanghai" , "Sao Paolo" , "Bishkek" , "Asmara" ] print (*cities) ['Shanghai', 'Sao Paolo', 'Bishkek', 'Asmara'] Shanghai Sao Paolo Bishkek Asmara Print each item on a separate line To print a list line-by-line use a for loop to cycle through each item. 'city ' is just a variable name and can be replaced with the traditional 'i ' or anything relevant to the context, such as 'colour ' in a list of colours or 'name ' in a list of people. cities = [ "Shanghai" , "Sao Paolo" , "Bishkek" , "Asmara" ] for city in cities: print (city) Shanghai Sao Paolo Bishkek Asmara Print separated items on one line To print separated data elements on the same line then you can use the end command which defines what should go after each item . The example below uses slashes but end = " , " would add comma and space between each element. cities = [ "Shanghai" , "Sao Paolo" , "Bishkek" , "Asmara" ] for city in cities: print (city, end = " / " ) Shanghai / Sao Paolo / Bishkek / Asmara / Print specific list items To print an element with a certain index , put the index in square brackets . But remember that the index starts at 0 not 1. cities = [ "Shanghai" , "Sao Paolo" , "Bishkek" , "Asmara" ] print ( "The first city is" , cities[0]) print (cities[2], "is the third city" ) The first city is Shanghai Bishkek is the third city Create a list of five different foods . Print all list items on one line . Then print each item on a different line . Finally print just the first and fifth items . Example solution: lettuce yoghurt tomato artichoke tuna lettuce yoghurt tomato artichoke tuna The first item is lettuce The fifth item is tuna Lists Task 1 (Five Foods ) Lists Task 2 (Four Numbers ) Create a list of four integer values . Print all list items on one line separated by colons . Example solutions: 345:123:932:758: 812:153:783:603: Add (Append / Insert) to a List Append items to the end of a list To add a new item to the end of a list use the .append() command. Write .append() after the name of your list, with the new data in brackets . pets = [ "dog" , "cat" , "hamster" ] pets.append( "rabbit" ) print (*pets) fillings = [ "ham" , "cheese" , "onion" ] extra = input ( "Enter another filling: " ) fillings.append(extra) print ( "Your sandwich:" , *fillings) dog cat hamster rabbit Enter another filling: lettuce Your sandwich: ham cheese onion lettuce Insert items to a specific index Use the insert command to place an item in a specific position within the list. Remember that Python counts from 0 so the medals example below puts "silver" as index 2 , which is actually the 3rd item . medals = [ "platinum" , "gold" , "bronze" ] medals.insert(2, "silver" ) print (*medals) names = [ "Stacy" , "Charli" , "Jasper" , "Tom" ] name = input ( "Enter a name: " ) position = int ( input ( "Enter an index: " )) names.insert(position,name) print (*names) platinum gold silver bronze Enter a name: Lena Enter an index: 0 Lena Stacy Charli Jasper Tom Enter a name: Pat Enter an index: 3 Stacy Charli Jasper Pat Tom Use a loop to add items to a list A for loop can be used to add a certain number of items to a list. A while loop can be used to keep adding values until a certain value (e.g. ' stop ' or ' end ') is input. animals = [ ] for i in range (4): animal = input ( "Enter an animal: " ) animals.append(animal) print ( "\nAnimals:" , *animals) animals = [ ] while True : animal = input ( "Enter an animal: " ) if animal == "stop" : break else : animals.append(animal) print ( "\nAnimals:" , *animals) Enter an animal: lion Enter an animal: horse Enter an animal: hyena Enter an animal: squirrel Animals: lion horse hyena squirrel Enter an animal: rhino Enter an animal: gazelle Enter an animal: deer Enter an animal: stop Animals: rhino gazelle deer Example solution: Lists Task 3 (Favourite Musicicans ) Create a list of three musicians or bands you like . Print the list . Then append two new bands using two inputs . Print the list again. Use the sandwich filling example for help. Musicians I like: Lana Del Rey Devon Cole Elly Duhé Enter another musician: Charli XCX Enter another musician: Kenya Grace Musicians I like: Lana Del Rey Devon Cole Elly Duhé Charli XCX Kenya Grace Lists Task 4 (Missing 7 ) Create a list of numbers in order from 1 to 10 but miss out 7 . Use the insert command to add 7 in the correct place . Print the list before and after you insert 7. Example solution: 1 2 3 4 5 6 8 9 10 1 2 3 4 5 6 7 8 9 10 Lists Task 5 ('Land' Countries ) Use a while True loop to input countries that end in 'land' until the word 'finish ' is input . Print the list at the end. Note: You do not need to check if the countries entered are correct. There are also more than four. Example solution: Enter a country ending in 'land': Iceland Enter a country ending in 'land': Poland Enter a country ending in 'land': Switzerland Enter a country ending in 'land': Thailand Enter a country ending in 'land': finish Country list: Iceland Poland Switzerland Thailand Delete (Remove/Pop) from a List Delete items with a specific value To delete data with a certain value use the .remove() command, with the value in brackets . trees = [ "fir" , "elm" , "oak" , "yew" ] trees.remove( "elm" ) print (*trees) fir oak yew trees = [ "fir" , "elm" , "oak" , "yew" ] tree = input ( "Select a tree to remove: " ) trees.remove(tree) print (*trees) Select a tree to remove: oak fir elm yew Delete items with a specific index To delete data in a specific position in your list use the .pop() command, with the position in the brackets . Remember that indexes start at 0 so .pop(0) removes the first item . Negative values start from the end of the list , so -1 is the final item and -2 is the second last item and so on. kitchen = [ "plate" , "cup" , "spoon" , "jug" ] kitchen.pop(0) print (*kitchen) kitchen = [ "plate" , "cup" , "spoon" , "jug" ] kitchen.pop(-2) print (*kitchen) kitchen = [ "plate" , "cup" , "spoon" , "jug" ] index = int ( input ( "Select an index: " )) kitchen.pop(index) print (*kitchen) cup spoon jug plate cup jug Select an index: 1 plate spoon jug Delete all items in a list To delete data in a list use the .clear() command. insects = [ "ant" , "bee" , "wasp" ] insects.clear() insects.append( "hornet" ) print (*insects) hornet Lists Task 6 (Day Off ) Example solution: Create a list with the five week days . Ask the user to input a weekday and remove that day from the list. Print the list. Which day do you want off? Tuesday Your new days of work: Monday Wednesday Thursday Friday Lists Task 7 (May and October ) Create a list with the twelve months in order . Delete May and then October using the pop command by referring to their indexes in the list. Print the list. Note: Be aware the index of each month after May will change when May is popped from the list. Example solution: January February March April June July August September November December Finding the Length of a List To find the length of a list use the len function. You can create a separate variable for the length (shown in the first example below) or use the len command directly (second example). states = [ "Maine" , "Utah" , "Ohio" , "Iowa" ] length = len (states) print ( "There are" , length , "states in the list." ) states = [ "Maine" , "Utah" , "Ohio" , "Iowa" ] print ( "There are" , len (states), "states in the list." ) There are 4 states in the list. Lists Task 8 (Q Words ) Use a while True loop to input words beginning with q until the word ' stop ' is entered. Then use len to find the length of the list and print this value. Note: You do not need to check if the entered words actually start with q. Example solution: Input a Q word: question Input a Q word: quick Input a Q word: quiet Input a Q word: quandry Input a Q word: stop You wrote 4 Q words! Cycle Through List Items A for loop can be used to cycle through each item in a list. The following examples present some ways that this may be used. This program uses a for loop to add a word (David) before each list item. davids = [ "Beckham" , "Attenborough" , "Schwimmer" , "Tennant" , "Lynch" ] for i in range (5): print ( "David" , davids[i]) David Beckham David Attenborough David Schwimmer David Tennant David Lynch An if statement can be used within a for loop to check the value of each item . The example below checks how many items are 'medium'. sizes = [ "small" , "medium" , "small" , "large" , "medium" , "small" ] count = 0 for i in range (6): if sizes[i] == "medium" : count = count + 1 print ( "There were" ,count, "medium choices." ) There were 2 medium choices. The program below uses a while loop to allow entries until 'stop ' is input then a for loop to check the value of each item . Because the final length of the list is not known when the program starts, the len command is used in the range of the for loop . sports = [] fcount = 0 rcount = 0 while True : option = input ( "Choose football or rugby: " ) sports.append(option) if option == "stop" : break for i in range ( len (sports)): if sports[i] == "football" : fcount = fcount + 1 elif sports[i] == "rugby" : rcount = rcount + 1 print ( "\nResults:" ,fcount, "people chose football and" ,rcount, "chose rugby." ) Choose football or rugby: rugby Choose football or rugby: rugby Choose football or rugby: football Choose football or rugby: rugby Choose football or rugby: football Choose football or rugby: stop Results: 2 people chose football and 3 chose rugby. Lists Task 9 (Over 25 ) Create a list with the following eight numbers: 13, 90, 23, 43, 55, 21, 78, 33 Use a for loop to cycle through the list and check if each item is over 25 . Use a count variable to increase by 1 if the number is over 25. At the end print how many numbers are over 25 - there are five . Example solution: 5 numbers are over 25. Lists Task 10 (Favourite Lesson ) Use a while True loop to keep inputting school subjects until ' done ' is entered. Keep a count of how many times ' Maths ' is entered. Print the total number of people who entered maths. Example solution: Enter a subject: English Enter a subject: Maths Enter a subject: Art Enter a subject: Maths Enter a subject: History Enter a subject: done There were 2 people who chose maths. Sorting Lists The .sort() command will sort elements in a list into alphabetical order (if a string ) or numerical order (if a number ). names = [ "Robb" , "Jon" , "Sansa" , "Arya" , "Bran" , "Rickon" ] print ( "Original:" , *names) names.sort() print ( "Sorted:" , *names) Original: Robb Jon Sansa Arya Bran Rickon Sorted: Arya Bran Jon Rickon Robb Sansa numbers = [56,98,23,12,45] numbers.sort() print (*numbers) 12 23 45 56 98 The .sort() command can be used to sort values in descending order by including reverse = True in the brackets. names = [ "Robb" , "Jon" , "Sansa" , "Arya" , "Bran" , "Rickon" ] print ( "Original:" , *names) names.sort(reverse = True ) print ( "Sorted:" , *names) Original: Robb Jon Sansa Arya Bran Rickon Sorted: Sansa Robb Rickon Jon Bran Arya numbers = [56,98,23,12,45] numbers.sort(reverse = True ) print (*numbers) 98 56 45 23 12 Lists Task 11 (Sorted Fruit ) Example solution: Use a for loop to append six fruits to an empty list. Sort the list into alphabetical order and print it. Enter a fruit: strawberry Enter a fruit: kiwi Enter a fruit: lemon Enter a fruit: pear Enter a fruit: orange Enter a fruit: mango Sorted fruit: kiwi lemon mango orange pear strawberry Searching Through Lists A simple if statement can be used to see if a certain value appears within a list. names = [ "Alex" , "Bill" , "Charlie" , "Darla" ] name = input ( "Enter a name: " ) if name in names: print ( "Yes," , name , "is in the list." ) else : print ( "Sorry," , name , "is not in the list." ) Enter a name: Bill Yes, Bill is in the list. Enter a name: Sadie Sorry, Sadie is not in the list. Lists Task 12 (Packed Suitcase ) Example solutions: Create a list with five items to take on holiday. Ask the user to input an item and use an if statement to check if it is or isn't in the list. What should I pack? sun cream I've already packed sun cream What should I pack? toothpaste Whoops! I forgot to pack toothpaste Calculating the Sum of a List To calculate the sum of a list of numbers there are two methods. Using Python's built-in sum function : numbers = [1,4,2,3,4,5] print ( sum (numbers)) Both methods will result in the same output : 19 Using a for loop to cycle through each number in the list and add it to a total . numbers = [1,4,2,3,4,5] total = 0 for number in numbers: total = total + number print (total) Lists Task 13 (Sum and Average ) Example solution: Use a for loop to ask the user to input 5 numbers and append each to a list. Use the sum command to output the total and use it calculate the average . Enter a number: 6 Enter a number : 7 Enter a number : 6 Enter a number : 9 Enter a number : 4 The total is 32 The average is 6.4 Extending a List .extend() can be used in a similar way to .append() that adds iterable items to the end of a list . This commands works well with the choice command (imported from the random library ) to create a list of characters that can be randomly selected. The code below adds a lowercase alphabet to an empty list and then, depending on the choice of the user, adds an uppercase alphabet too. The choice command is used in a loop to randomly select 5 characters. Using .extend() to make a random 5-character code from random import choice list = [] list. extend ( "abcdefghijklmnopqrstuvwxyz" ) upper = input ( "Include uppercase letters? " ) if upper == "yes" : list. extend ( "ABCDEFGHIJKLMNOPQRSTUVWXYZ" ) code = "" for number in range (5): letter = choice (list) code = code + letter print ( "Your five character code is" , code) Possible outputs: Include uppercase letters? yes Your five character code is yPfRe Include uppercase letters? yes Your five character code is GJuQw = Include uppercase letters? no Your five character code is gberv Extend treats each character as an indidual item whereas append adds the whole string as a single entity . Most of time append would be used, but extend is suitable for a password program as additional individual characters can be added to a list depending on the parameters (e.g. lowercase letters, uppercase letters, numbers and special characters). list = [] list. extend ( "ABCD" ) list. extend ("EFGH" ) print (list) list = [] list. append ( "ABCD" ) list. append ("EFGH" ) print (list) ['A','B','C','D','E','F','G','H'] ['ABCD' , 'EFGH'] = = Practice Task 14 Use the code above (for a 5-character code ) to help you make a password generator . Ask the user if they want uppercase letters , numbers and special characters and use the extend command to add them to a list of characters if they type yes (you should extend lowercase characters into an empty list regardless, like in the code above). Use a for loop and the choice command (imported from the random library) to randomly generate a 10-character password . Example solutions: Include uppercase letters? yes Include numbers? yes Include special characters? yes Your new password is RjWSbT&gW5 Include uppercase letters? no Include numbers? yes Include special characters? no Your new password is hdf8se9y2w ⬅ Section 7 Practice Tasks 8b - 2D Lists ➡

Learn about required internal hardware including the CPU, motherboard and PSU. Find out about ports and expansion cards. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification. 1.2 Computer Components Exam Board: OCR Specification: 2016 - Unit 1 This page describe the various components inside of computer systems . The first three are necessary in every type of computer: Processor Motherboard Power Supply Unit The main role of a processor is to manage the functions of a computer system by processing data and instructions . The primary processor of each computer system is the Central Processing Unit ( CPU ). A processor is attached to the motherboard using a connection point called a CPU socket . The motherboard is the main circuit board of a computer on which components such as the CPU and ROM are connected . The motherboard contains PCI slots for expansion cards and ports for external devices to be connected . The power supply unit (PSU ) converts electricity from AC (Alternating Current) from the mains power supply to DC (Direct Current) which the computer system can use . The PSU of desktop computers is internal whereas portable devices require an external 'charger '. Memory Computer memory is split into two types - volatile and non-volatile . Volatile storage is temporary (data is lost whenever the power is turned off ). Non-volatile storage saves the data even when not being powered , so it can be accessed when the computer is next on and can be stored long-term . Random Access Memory (RAM) Read-Only Memory (ROM) Cache Memory RAM is volatile (temporary) storage that stores all programs that are currently running . RAM also stores parts of the operating system to be accessed by the CPU. RAM is made up of a large number of storage locations, each can be identified by a unique address . ROM is non-volatile storage that cannot be changed . ROM stores the boot program / BIOS for when the computer is switched on. The BIOS then loads up the operating system to take over managing the computer. Cache memory is volatile (temporary) storage that stores frequently accessed data . It is very quick to access and faster than other types of memory like RAM because it is stored on the processor itself. RAM ( R andom A ccess M emory) ROM ( R ead O nly M emory) Cache Memory Secondary Storage Magnetic Storage Optical Storage Optical Storage Characteristics: X - Low CAPACITY : 700 MB (CD ), 4.7 GB (DVD ), 25 GB (Blu-ray ). X - Not DURABLE because discs are very fragile and can break or scratch easily. ✓ - Discs are thin and very PORTABLE . X - Optical discs have the Slowest ACCESS SPEED . Magnetic Disks are spelled with a k and Optical Discs have a c. Magnetic Storage Characteristics: ✓ - Large CAPACITY and cheaper per gigabyte than solid state . X - Not DURABLE and not very PORTABLE when powered on because moving it can damage the device. ✓ - Relatively quick ACCESS SPEED but slower than Solid State . Optical storage uses a laser to project beams of light onto a spinning disc, allowing it to read data from a CD , DVD or Blu-Ray . This makes optical storage the slowest of the four types of secondary storage. Disc drives are traditionally internal but external disc drives can be bought for devices like laptops. A magnetic hard disk drive (HDD ) is a common form of secondary storage within desktop computers. A read/write head moves nanometres above the disk platter and uses the magnetic field of the platter to read or edit data. Hard disk drives can also be external and connected through a USB port . An obsolete (no longer used) type of magnetic storage is a floppy disk but these have been replaced by solid state devices such as USB sticks which are much faster and have a much higher capacity. Another type of magnetic storage that is still used is magnetic tape . Magnetic tape has a high storage capacity but data has to be accessed in order (serial access ) so it is generally only used by companies to back up or archive large amounts of data . Solid State Storage Cloud Storage When you store data in 'the cloud ', using services such as Google Drive, 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 typically free for a certain amount of storage and users can buy more storage space when they need it - the scalable nature of this storage type makes it very flexible for businesses. 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 is also known as 'virtual storage ' because the data is saved remotely , freeing up physical storage space for users on their own devices . There are no moving parts in solid state storage . SSD s (Solid State Drives ) are replacing magnetic HDDs (Hard DIsk Drives) in modern computers and video game consoles because they are generally quieter , faster and use less power . A USB flash drive ( USB stick ) is another type of solid state storage that is used to transport files easily because of its small size. Memory cards , like the SD card in a digital camera or a Micro SD card in a smartphone , are another example of solid state storage. Solid State Characteristics: X - High CAPACITY but more expensive per gigabyte than magnetic . ✓ - Usually DURABLE but cheap USB sticks can snap or break . ✓ - The small size of USB sticks and memory cards mean they are very PORTABLE and can fit easily in a bag or pocket. ✓ - Solid State storage has the fastest ACCESS SPEED because they contain no moving parts . 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 . Storage Protocols SCSI ( Small Computer System Interface ) is a protocol (set of rules) for attaching external devices to a computer system, such as a printer, storage drive or scanner. SAS ( Serial Attached SCSI ) is an improved version of SCSI that enables many more external devices (up to 128) to be connected at the same time to a computer system. Expansion Cards Expansion cards are dedicated circuit boards with a specific purpose that are attached to the motherboard . Most of the following expansion cards can also exist as integrated components on the motherboard, rather than a separate card. Graphics Card Sound Card Processes graphical data (e.g. videos or animations) and converts it into a displayable output on a monitor . Network Interface Card (NIC) 0010 1011 0101 0101 0110 0111 0101 0001 0101 Sound cards convert analogue sound waves into digital data (binary) when inputting audio through a microphone. Sound cards also convert digital data (binary) into analogue sound waves to output audio through speakers or headphones. 0010 1011 0101 0101 0110 0111 0101 0001 0101 Allows computers to connect to networks (such as the Internet ) and enables them to transfer data to other computers. Transfers data between servers across a network. Fibre channel allows for quick transfer speeds and is primarily used to connect data storage to servers in large data centres. Fibre Channel Card Storage Controller Card Required for the computer to manage and use any attached storage devices . Ports A port is the interface between external devices and the computer . Ports allow data to be transferred from and to these devices. USB Port Connects storage devices such as USB sticks or external hard drives . Connects input devices such as a keyboard or mouse, as well as other devices for data transfer such as a camera or smartphone. Ethernet Port Connects computers to network devices such as a modem or router, allowing access to the internet . FireWire Port Developed for Apple products, FireWire transfers data at a high speed from devices such as camcorders and external hard drives . FireWire supports isochronous devices , meaning data is sent in a steady , continuous stream . SATA Port Allows fast data transfer to external HDD , SSD or optical drives . SD Port Enables data from an SD card to be transferred from a device like a camera to the computer. Micro SD Port Allows data from a micro SD card to be transferred from devices such as smartphones , tablets and handheld games consoles to a computer. Q uesto's Q uestions 1.2 - Computer Components: Vital Components: 1. Describe the purpose of the following components : a. The CPU (Central Processing Unit ) [2 ] b. The motherboard [2 ] c. The PSU (Power Supply Unit ) [2 ] Primary Memory: 2a. What is the difference between primary and secondary memory ? [2 ] 2b. What is the difference between volatile and non-volatile storage ? [2 ] 2c. For each of the three types of primary memory , describe its role and give an example of what it can store. [6 ] Secondary Storage: 3a. For magnetic , optical and solid-state storage rank these three secondary storage mediums in terms of capacity , durability , portability and speed . [9 ] 3b. For the following scenarios justify which secondary storage medium should be used and why it is the most appropriate : Sending videos and pictures to family in Australia through the post. [3 ] Storing a presentation to take into work. [3 ] Storing project files with other members of a group to work on together. [3 ] Backing up an old computer with thousands of file to a storage device. [3 ] Additional Components: 4a. State the purpose of five different expansion cards . [5 ] 4b. What is the purpose of the motherboard ? [2 ] Ports: 5a. Describe the six different ports . [6 ] 5b. What is the difference between SCSI and SAS ? [2 ] 1.1 - Computer Hardware Topic List 1.3 - Computer System Types

Learn about the three main types of secondary storage - magnetic, optical and solid-state. Also, learn about the characteristics of secondary storage media including reliability and durability. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 2.2: Secondary Storage Exam Board: OCR Specification: J277 Watch on YouTube : Secondary Storage Six Characteristics Magnetic Storage Optical Storage Solid State Storage Secondary storage is non-volatile storage used to save and store data that can be accessed repeatedly. Secondary storage is not directly embedded on the motherboard (and possibly even external ) and therefore further away from the CPU so it is slower to access then primary storage . Storage Characteristics you should know: CAPACITY : The maximum amount of data that can be stored on the device. DURABILITY : The strength of the device, to last without breaking . PORTABILITY : How easy it is to carry the device around . ACCESS SPEED : How quickly data on the device can be read or edited . COST : The average price it costs to purchase the storage device. RELIABILITY : The likelihood of the device continuing to perform well over time . Magnetic Storage A magnetic hard disk drive (HDD ) is the most common form of secondary storage within desktop computers. A read/write head moves nanometres above the disk platter and uses the magnetic field of the platter to read or edit data. An obsolete (no longer used) type of magnetic storage is a floppy disk but these have been replaced by solid state devices such as USB sticks which are much faster and have a much higher capacity. Another type of magnetic storage that is still used is magnetic tape . Magnetic tape has a high storage capacity but data has to be accessed in order (serial access ) so it is generally only used by companies to back up or archive large amounts of data . Magnetic Storage Characteristics (Hard Disk Drive): ✓ - Large CAPACITY and cheaper COST per gigabyte than solid state . ✓ - Modern external HDDs are small and well protected so they are DURABLE and PORTABLE , however because of the moving parts, they should not be moved when powered on because it can damage the device. X - Slower ACCESS SPEED than solid state but faster than optical storage . Optical Storage Optical storage uses a laser to project beams of light onto a spinning disc, allowing it to read data from a CD , DVD or Blu-Ray . This makes optical storage the slowest of the four types of secondary storage. Disc drives are traditionally internal but external disc drives can be bought for devices like laptops. Magnetic Disks are spelled with a k and Optical Discs have a c. Optical Storage Characteristics: X - Low CAPACITY : 700 MB (CD ), 4.7 GB (DVD ), 25 GB (Blu-ray ). X - Not DURABLE because discs are very fragile and can break or scratch easily. ✓ - Discs are thin and very PORTABLE . Also very cheap to buy in bulk. X - Optical discs have the Slowest ACCESS SPEED . Solid State Storage There are no moving parts in solid state storage. SSD s (Solid State Drives ) are replacing magnetic HDDs (Hard DIsk Drives) in modern computers and video game consoles because they are generally quieter , faster and use less power . A USB flash drive ( USB stick ) is another type of solid state storage that is used to transport files easily because of its small size. Memory cards , like the SD card in a digital camera or a Micro SD card in a smartphone , are another example of solid state storage. Solid State Characteristics: X - More expensive COST per gigabyte than magnetic . ✓ - Usually DURABLE but cheap USB sticks can snap or break . ✓ - The small size of USB sticks and memory cards mean they are very PORTABLE and can fit easily in a bag or pocket. ✓ - Solid State storage have a high CAPACITY and the fastest ACCESS SPEED because they contain no moving parts . Q uesto's Q uestions 2.2 - Secondary Storage: 1. Rank magnetic , optical and solid-state storage in terms of capacity , durability , portability , speed and cost . For example, magnetic has the highest capacity , then solid-state, then optical. This could be completed in a table . [15 ] 2. Justify which secondary storage should be used in each scenario and why it is the most appropriate: a. Sending videos and pictures to family in Australia through the post . [ 2 ] b. Storing a presentation to take into school . [ 2 ] c. Storing project files with other members of a group to work on together . [ 2 ] d. Backing up an old computer with thousands of files to a storage device. [ 2 ] 2.1 - Primary Storage Theory Topics 2.3 - Data Units

Learn about why testing is needed, types of testing, types of test data and types of error. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 3.2: Testing Exam Board: OCR Specification: J277 Watch on YouTube : Purpose of Testing Types of Error Test Data The main purpose of testing is to ensure that a program works correctly no matter what input has been entered by the user. Other reasons to test a program include ensuring the user requirements have been met , errors have been removed and the program doesn't crash while running . Types of Testing Iterative Testing Iterative testing takes place during program development . The programmer develops a module , tests it and repeats this process until the module works as expected . Final Testing Final testing, also known as terminal testing , takes place after development and before the program is released to the end user. This testing takes place once all modules have been individually tested to ensure the whole program works as originally expected. Programming Errors Syntax Error Logical Error A syntax error is a mistake in the grammatical rules of the programming language , such as an incorrect spelling of a command word. A syntax error will prevent the program from being compiled and executed . Examples: Incorrect Spelling: pront ( "hello" ) Incorrect punctuation: print ( "hello" ( A logic error is a mistake made by the programmer - the program runs without crashing but will display the wrong output . Examples: Incorrect calculation: total = num1 - num2 print (total) Incorrect variable printed: age = 16 name = "Steve" print ( "Nice to meet you" , age) Test Data Test data is used to test whether a program is functioning correctly . It should cover a range of possible and incorrect inputs , each designed to prove a program works or to highlight any flaws . Four types of test data are: Normal data - Sensible data that the program should accept and be able to process . Boundary data - Data at the extreme boundary of any data ranges. Invalid data - Data of the correct data type that does not meet the validation rules (e.g. outside of the range). It should not be accepted . Erroneous data - Data of the wrong data type that the program cannot process and should not accept . Q uesto's Q uestions 3.2 - Testing: 1. Give 3 reasons why programs are tested . [ 3 ] 2. What is the difference between iterative and final testing ? [ 2 ] 3a. What is a syntax error ? Give an example . [ 2 ] 3b. What is a logical error ? Give an example . [ 2 ] 4. State and describe the four types of test data . [ 6 ] 3.1 - Defensive Design Theory Topics 4.1 - Boolean Logic

Learn about designs, documents and diagrams related to human-computer interaction including processing and data handling, data flow diagrams (level 0 and level 1), flowcharts and user interface designs (visualisation and wireframe diagrams). 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) 5.3 - Human Computer Interface Designs, Documents and Diagrams Watch on YouTube : Data flow diagrams Flowcharts Visualisation diagrams Wireframe diagrams There are four types of documents / diagrams you need to know that can be used to design human-computer interfaces : data flow diagrams (DFDs ), flowcharts , visualisation diagrams and wireframe designs . For each type of diagram , you need to know its components and conventions , when it is appropriate for use , and how to create it . Each diagram is also effective for different uses and you must be able to consider how specific diagrams can be made more effective . Human-Computer Interface Diagrams Data Flow Diagrams A data flow diagram (DFD ) is a visual representation of how data is transferred within a system or organisation . They do not show decision logic or sequencing , but focus on where data comes from , where it goes and how it is processed . DFDs are typically categorised into Level 0 and Level 1 formats, which differ based on complexity . Flowcharts A flowchart is a diagram that shows the sequence of steps in a process using specific symbols . Flowcharts can be used as a project planning tool (section 3.2 ) to visualise workflows , task order and decision-making paths . It is also useful as a human-computer interface diagram to show the steps and decisions users may take as they interact with the application . The video says ' 3.2d ' because flowcharts also appear in section 3.2 as a project planning tool . Visualisation Diagrams Visualisation diagrams are graphical representations used to show the layout , structure and appearance of a software application's interface . They're often used for planning , design and feedback purposes. Traditionally, they would be drawn on paper in pencil and annotated , but modern diagrams are mocked up on a computer so they can be easily shared with team members and clients . Wireframe Diagrams Wireframe diagrams are basic visual guides used to represent the structure and layout of a user interface (UI ) without any design styling . They focus on function , layout and interaction , not aesthetics . Wireframe diagrams are used in the early design stages to plan the UI layout before visual design begins. Q uesto's Q uestions 5.3 - Human Computer Interface Designs, Documents & Diagrams: 1. Explain what the purpose of data flow diagrams are, the difference between Level 0 and Level 1 and what makes them effective . [6 ] 2. Draw a wireframe diagram for the YouTube homepage . [3 ] 3. Explain how visualisation diagrams are created and how they can be made more effective . [ 5 ] The first type of flowchart , the ' flow process chart ', was developed by engineers Frank and Lillian Gilbreth in 1921 . The book (and original movie ) ' Cheaper by the Dozen ' is about this couple . D id Y ou K now? 5.2 - Visual Design Considerations Topic List 6.1 - Job Roles

Learn how to input numbers in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 2B - Inputting Numbers Inputting Whole Numbers in Python To enter whole numbers then you must use the int command. int stands for integer (a whole number ) and is typed before input – don’t forget the double brackets at the end . age = int ( input ( "How old are you? " )) print ( "Have you really lived for " , age , "years?" ) = How old are you? 99 Have you really lived for 99 years? Inputting Numbers Task 1 ( Zoo) Type an input line (with int ) to ask the user how many times they’ve been to the zoo . Print a reply that uses the zoo variable (their answer). Example solution: How many times have you been to the zoo? 3 You've been to the zoo 3 times? I love animals! Inputting Decimal Numbers in Python Using float instead of int allows a decimal number to be entered instead. Again, don’t forget the double brackets at the end . miles = float ( input ( "How far have you walked today? " )) print ( "You really walked for " , miles , "miles? Wow!" ) = How far have you walked today? 5.6 You really walked for 5.6 miles? Wow! Inputting Numbers Task 2 ( Height ) Type an input line (with float ) to ask the user their height in metres. Print a reply that uses the height variable (their answer). Example solution: What is your height in metres? 1.82 You are 1.82 metres tall? Wow! ⬅ 2a - Inputting Text Sect ion 2 Practice Tasks ➡

Learn how to handle numbers in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 9b - Number Handling Rounding Numbers The round() command is used to round a value to a certain number of decimal places . Type your variable into the round command brackets, add a comma and state the number of decimal places to round to. Fixed Decimal Places (Currency) The round function will remove any trailing 0s , for example 30.1032 will become 30.1 even if you specified to round to 2 decimal places . Instead, you can use an f -string and write :.2f after a bracketed variable to use exactly 2 decimal places . The number can be changed from 2. books = int ( input ( "How many books would you like to buy? " )) total = books * 3.99 print ( f"The total is £ {total:.2f} - Thanks for your order!" ) How many books would you like to buy? 10 The total is £39.90 - Thanks for your order! How many books would you like to buy? 100 The total is £399.00 - Thanks for your order! Practice Task 1 Ask the user to enter any large number. Ask the user to enter another large number. Divide the two numbers and print the answer to 3 decimal places. Example solution: Using Numbers as Strings The following techniques all require the integer to be converted into a string first using the str command. Just like a string, you can shorten a variable to only display a certain length . Remember that Python starts at zero . You can select a specific digit in the same manner as when selecting characters in a string. If you want to use your variable as an integer again later you would need to convert it from a string to an integer using the int command. Again, reversing a number is the same as reversing a string. You can also use other string handling methods such as .startswith() or .endswith() Practice Task 2 Ask the user to enter a 10 digit number. Select the 2nd and 8th digits and add them together. Print the total. Example solution: ⬅ 9a - String Handling Section 9 Practice Tasks ➡

Learn how to embed images into your HTML web page using the img tag. Learn how to resize an image to your desired width and height. 5. Images HTML Guide Watch on YouTube: Images can be added to your web page to make it more visual. The guide below shows you how to find a picture online, download it and place it in your web page. Find & Save the Image Firstly you can perform a Google Image search to find a picture that you like. As an ethical Computer Scientist, you should be searching for copyright free images. Click on Tools and then Usage Rights to change it to 'Labeled for reuse'. Choose an appropriate image and download it to the same folder as your html file. Save the image in the same folder as where your HTML file is saved . If you don't do this, your image won't work . If you are using a school computer and the image automatically downloads , without giving you the option to rename it and save it, click on 'Show in folder' and move it to the folder where your HTML file is . Make sure that the image is saved in the exact same folder as your HTML file and that is has a suitable name . Create the Image Tag The tag for images does not have an end tag - it is all written within one set of angle brackets. src stands for source . You must type the image exactly as it is saved , including the file type (e.g. .jpg or .png). Don't forget the speech marks either. Create the img tag, using the exact name of the image you downloaded. Change the Image Size You can directly state the width and height of the image by defining the style within the image tag. If your image is too large or too small, change the size of it yourself. Next it is time to organise the web page further so it looks more like a professional site. 4. Hyperlinks HTML Guide 6. Organisation

Learn about the three principles of information security - confidentially, integrity and availability. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification for Unit 2 (Global Information). 6.1 - Security Principles Exam Board: OCR Specification: 2016 - Unit 2 There are three key principles of data security that are protected in legislation such as the Data Protection Act (2018 ). Organisations storing personal or sensitive information must ensure that these three principles are upheld at all times . Confidentiality What it means: Information should only be accessed by individuals or groups with the authorisation to do so. How to uphold this principle: An organisation should use protection measures like usernames and passwords to ensure that only authorised people can access the sensitive data. Tiered levels of access or permissions can also limit who has access to the data. Integrity What it means: Information is maintained so that it is up-to-date , correct and fit for purpose . How to uphold this principle: Organisations should carry out regular data maintenance to update information (e.g. confirm contact details once a year). If storing data in a spreadsheet or database, record-locking should be used so that only person can edit at a time, preventing the data from becoming incorrect. Availability What it means: Information is available to the individuals or groups that need to use it. It should only be available to those who are authorised . How to uphold this principle: Staff should have the correct privileges so that they can easily access data when required. Data could be stored online , e.g. cloud storage so that it is available remotely using an internet connection. Data must also be kept safe from unauthorised access . Staff should not make additional copies of information which could be lost or stolen. Q uesto's Q uestions 6.1 - Security Principles: 1a. Describe what is meant by ' confidentiality ' . [1 ] 1b. Explain two ways that an organisation can keep data confidential . [4 ] 2a. Describe what is meant by ' integrity ' . [1 ] 2b. Explain two ways that an organisation can preserve the integrity of its data . [4 ] 3a. Describe what is meant by ' availability ' . [2 ] 3b. Explain two ways that an organisation can keep its data available . [4 ] 5.2 - Data Flow Diagrams Topic List 6.2 - Risks