Learn about the eight rules of Boolean algebra expressions. Based on the 2020 Eduqas (WJEC) GCSE specification. 2.2: Boolean Algebra Exam Board: Eduqas Specification: 2020 Boolean algebra is used to simplify Boolean expressions so that they are easier to understand. Because calculations can use dozens of logical operators, they are simplified in Boolean Algebra using symbols rather than words. Take your time and don't panic. In an exam, you might get a list of identities (rules) to use. One tip to solving boolean algebra is to imagine that A and B are real expressions . In the examples on this page, imagine: A represents the true statement 'the sky is blue' B represents the true statement 'grass is green' 0 always means FALSE 1 always means TRUE Boolean Symbols A = NOT A A . B = A AND B A + B = A OR B Boolean Identities are the rules that are used to simplify Boolean expressions. Each identity (law) has an AND form and an OR form , depending on whether AND or OR is being used . Commutative Law AND form: OR form: This law just switches the order of the expressions . For example, 'sky is blue' AND 'grass is green' makes logical sense in either order. Idempotent Law = AND form: OR form: This law removes repetition . Complement Law NOT AND form: The sky cannot be blue and not blue at the same time, so it must be 0 (FALSE). OR form: The sky is blue or not blue must be 1 (TRUE) as it has to be one of these options. Identity Law AND form: 1 represents TRUE . Both statements are true so it can be simplified as just A . OR form: 0 represents FALSE . Because A is true, you can ignore the false statement and it can be simplified as just A . Annulment Law AND form: 0 represents FALSE . Even though A is true, a statement cannot be true and false at the same time, so it must be 0 (FALSE). OR form: 1 represents TRUE . Both statements are true so this can be simplified as just 1 (TRUE). Absorption Law AND form: OR form: Absorption law reduces a bracket into one value. If the first A is true then both values in the brackets are true but if the first A is false then both values are false. Therefore this equation relies entirely on A and can be simplified as just A . Association Law ( ) AND form: OR form: This law separates a bracketed expression that uses the same operator inside and outside the brackets by removing the brackets . Distribution Law ( ) = ( ) ( ) AND form: OR form: The value outside of the bracket (e.g. A) is multiplied by both values inside the brackets , forming two new brackets which are linked by the logical operator formerly within the bracket . Notice that the logical operator role is switched , e.g. AND switches from within the brackets, to between the new brackets. A note about distribution law - The three values may not necessarily be three separate letters (e.g. A, B and C) as B or C could be NOT A for example. A NOT value is considered a new value , e.g. A and Ā are separate values. Another note about distribution law - Exam questions may ask you to perform the distribution law (or any law) in reverse . For example, converting (A+B) . (A+C) into A + (B.C) Boolean Algebra Exam Question Some previous exam questions have listed helpful laws for you but others haven't, so you should know each individual law . In a previous exam, the candidates were given three general laws to help them . P, Q and R just represent three different values. P . 1 = P (Identity Law) P . Q + P . R = P. (Q + R) (Distribution Law) P + P = 1 (Complement Law) Using the rules above , candidates were asked to simplify the following expression : X = A . B + A . B The general laws have been give n to you for a reason. You need to look at the laws provided and see which one currently matches the expression in front of you . If you look closely in this example, the second law is very similar to the expression you are asked to simplify so you can use it to make the first simplification, just swap P for A, Q for B and R for NOT B: Using this law P . Q + P . R = P. (Q + R) X = A . B + A . B simplifies as: X = A . (B + B) Now you need to see which of the three provided laws can be used with the current expression . The third law is very similar to the expression you now need to simplify further , just swap P for B and NOT P for NOT B: Using this law P + P = 1 X = A . (B + B) simplifies as: X = A . (1) And finally, there is one law left to use. The first law is very similar to the expression you now need to simplify further , just swap P for A. Using this law P . 1 = P X = A . (1) simplifies as: X = A You have now used all three laws and the expression is fully simplified . Remember - Look at the laws that you have been given and see which law matches your expression . Q uesto's Q uestions 2.2 - Boolean Algebra: 1. Draw the example equations and write a brief description of each of the eight Boolean laws : Commutative Law Idempotent Law Complement Law Identity Law Annulment Law Absorption Law Associate Law Distributive Law 2. Below are three Boolean identities: P . P = 0 (P + Q) . R = (P . R) + (Q . R) P + 0 = P Using the three rules above , simplify the following expression: X = (A + B) . Ā This law is called ' Inverse Law ' in the Eduqas 2016 teacher guidance but ' Complement Law ' in the 2020 specification. This law is called ' Zero and One Law ' in the Eduqas 2016 teacher guidance but ' Annulment Law ' in the 2020 specification. This law is called ' Associate Law ' in the Eduqas 2016 teacher guidance but ' Association Law ' in the 2020 specification. This law is called ' Distributive Law ' in the Eduqas 2016 teacher guidance but ' Distribution Law ' in the 2020 specification. 2.1 - Logical Operators Theory Topics 3.1 - Network Characteristics

The third part of a quick guide to the basics of Python aimed at Key Stage 3 students. Learn about creating and using inputs. Python - #3 - Inputs 1. Asking Questions Input means to enter data into a program. Use the input command to ask a question. You must save the answer into a suitably named variable using the = symbol. Task 1 - Create a new Python program and save the file as 3-Inputs.py Use the picture to help you ask what someone's name is. Run the program and type your name. When you run the program (F5) you can type your answer on any question line in the Python Shell . 2. Asking more Questions There is no limit to how many questions you can ask in Python. It is the most important way to interact with the user of your program. Task 2 - Ask two more questions on topics of your choice. 3. Using Variables in a Sentence When we have printed the answers so far, they have not been very informative! You can print variables together with sentences so that they mean more. Use a comma ( , ) between variables and sentences . Task 3 - Use the pictures to help you add commas and sentences to your program to be more informative. BONUS: After I took the screenshot of my code I added in print lines in the two blanks spaces that print a line of dashes. Try to do the same to make your program easier to read. 4. Using Integers An integer is a whole number . When you are asking a question that you know will have a number for an answer , you need to add int ( before your input. Don't forget to add double close brackets at the end of the question line ! Task 4 - Underneath your previous questions (don't delete anything) ask 2 questions that will have numbers for answers. You must use int ( - see the image for help. Challenge Programs Use everything that you have learned on this page to help you create these programs... Challenge Task 1 - Funny Food Create a new Python program. Save it as ' 3-FunnyFood.py ' Add a comment at the top with your name and the date. Create a program that asks two questions, one for their favourite colour and one for their favourite food. Print a funny sentence using both of their answers. BONUS : Try to use only one print line. Remember: Break up variables in a print line by using commas. When you run it, it could look something like this: Challenge Task 2 - Trivia Question Create a new Python program. Save is as ' 3-Trivia.py ' Add a comment at the top with your name and the date. Create a program that asks the user a trivia question of your choice. Print the correct answer AND their answer. BONUS : Use only one print line. BONUS : Try to use only two lines in total . Remember: Break up variables in a print line by using commas. When you run it, it could look something like this: Challenge Task 3 - Getting to School Create a new Python program. Save it as ' 3-School.py ' Add a comment at the top with your name and the date. Create a program that asks two questions, one for how they get to school and one for how long it takes. Don't forget - use int( and then double close brackets for a number! Print an appropriate response that uses both of their answers. BONUS : Use two separate input lines. BONUS : Try to use only one print line . Remember: Break up variables in a print line by using commas. When you run it, it could look something like this: <<< #2 Variables #4 Calculations >>>

Learn how to create print statements in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 1a - Printing Printing in Python To output a message onto the screen, use the print command. Then place your message within brackets and speech marks . For example: print ( "Welcome to Python!" ) When you run the program, the text will print to the Python console: Welcome to Python! Printing Task 1 (Full Name & To Your Left) On the first line, print your first name and surname. On the next line, write another print statement to print t he name of the person (or thing) to your left. Example solution: Elsie Parker pencil case Printing over Several Lines One way of writing across multiple lines is to write several print commands like this: print ( "Welcome to...." ) print ( "Computer Science " ) print ( "Newbies!!! " ) = Welcome to .... Computer Science Newbies!!! However, when we program, we always want to make our code the most efficient it can be by using as few lines as possible . Therefore you can write \n within a printed statement to move it to the next line. Make sure you use \ and not / otherwise it will print the slash and not make a new line! print ( "Welcome to....\n Computer Science\n Newbies!!! " ) = Welcome to .... Computer Science Newbies!!! Both pieces of code display the same thing, but the second one is more efficient because it only uses one line. Printing Task 2 (Name, Colour, Movie) Use \n to write your name, favourite colour and favourite movie in only one line of code. Example solution: Matthew yellow Interstellar ⬅ Setting Up Python 1b - Comments ➡

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

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Learn about the tools of an integrated development environment (IDE) including the editor, error diagnostics and run-time environment. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). Exam Board: OCR Specification: J277 5.2: Integrated Development Environment Watch on YouTube : IDE Tools An IDE (Integrated Development Environment ) provides programmers with the following facilities (tools ) to help create programs : Editor The editor is software that allows a programmer to enter and edit source code . Editor features may include: Automatic formatting (e.g. automatic indentation). Automatic line numbering (this helps to identify exactly where an error has occurred). Automatic colour coding (e.g. Python IDLE turns loop commands orange and print commands purple). Statement completion (e.g. offering to auto-complete a command as the user is typing.) Error Diagnostics & Debugger Break point The programmer selects a specific line and the program displays the variable values at that point . The code can then be executed one line at a time to find exactly where the error occurs. This process is called single-stepping . Variable Watch / Watch Window cost Displays the current value of a selected variable . A variable can be watched line-by-line to see how the value changes . Trace Logs the values of variables and outputs of the program a s the code is executed line by line . Both tools are used to display information about an error when it occurs, such as the line it occurred on and the error type (e.g. syntax ). These tools may also suggest solutions to help the programmer to find and fix the error . Compilers & Interpreters Both tools convert the source code written by a programmer into machine code to be executed by the CPU. A compiler converts the entire source code into executable machine code at once . After compilation, the program can be run again without having to recompile each time. An interpreter converts source code into machine code line by line . An interpreter must reinterpret the code each time the program is required to run . See 5.1 for both types of translators. A runtime environment allows a program to run on a computer system. It checks for runtime errors and allows users to test the program . A runtime error occurs as the program is being executed , such as dividing a number by zero . A commonly used example is the Java Runtime Environment . This allows programmers to design a program on one platform ( using the programming language Java ) which allows the finished program to then be run on many others systems . A runtime environment enables the tools above such as a trace and breakpoint to be used. Run Time Environment Q uesto's Q uestions 5.2 - Integrated Development Environment: 1. Describe the purpose of each type of IDE tool : a. Editor b. Interpreter c. Compiler d. Error Diagnostics / Debugger e. Break point f. Variable Watch / Watch Window g. Trace h. Runtime Environment [ 2 each ] 5.1 - Languages & Translators Theory Topics

Learn about two important expansion cards that can be connected to the motherboard - graphics cards and sound cards - and how they work. Expansion Cards PCI slots What are expansion cards? Expansion cards are additional components that you plug into the motherboard’s expansion slots to add or enhance features . The slots are called PCI (on older computers ) or PCIe (on newer models ). Common types are graphics cards (video ), sound cards (audio ), network cards (internet ) and capture cards (streaming ). Graphics Card A graphics card processes images , videos and 3D graphics so they look smooth and realistic . It is used for gaming , video editing , 3D modelling and Virtual Reality (VR ). It has its own processor - the Graphics Processing Unit (GPU ) - and dedicated memory (VRAM ), so it doesn’t overload the CPU or RAM . Modern graphics cards can also handle tasks like artificial intelligence (AI ) and bitcoin mining . Graphics cards usually have a cooling system, like a fan , so it doesn't overheat. The graphics processing unit ( GPU ) is a chip that renders images and video. The graphics card has ports such as HDMI or DisplayPort to connect monitors or TVs. The PCIe connector allows the graphics card to slot onto the motherboard. Sound Card The DAC ( Digital-to-Analogue Converter ) converts digital data (1s and 0s) from the computer into analogue sound waves for speakers/headphones. The ADC ( Analogue-to-Digital Converter ) converts analogue input (like voice from a microphone) into digital data the computer understands. Jacks are small round sockets where you plug in audio devices like headphones, microphones, or speakers. The PCIe connector allows the sound card to slot onto the motherboard. A sound card improves the quality of audio input/output compared to the motherboard’s built-in sound . They are not needed by most users , because of the motherboard's built-in sound , but they are used by music production , gaming or professional audio work . It can support surround sound systems , high-quality microphones , and musical instruments using jacks (audio ports ). Integrated cards Built directly into the motherboard . Cheaper , uses less power and is good enough for basic tasks (e.g. web browsing , watching videos and office work ). Shares the computer’s RAM and processor (CPU ) instead of having its own . An example is integrated graphics on a laptop for browsing and schoolwork . Dedicated cards These are separate expansion cards (e.g. graphics card or sound card ) to connect to the motherboard 's PCIe slots . They usually have their own processor and memory (e.g. GPU & VRAM for graphics ). Much more powerful , ideal for gaming , video editing , 3D design or professional audio . Uses more power and costs more . KS3 Home

Learn about programming paradigms such as procedural language (e.g. Python), assembly language (including Little Man Computer) and object-oriented programming (OOP) language (e.g. Java). Methods of memory addressing (immediate, direct, indirect and indexed) are also covered. Based on the OCR H446 Computer Science A-Level specification. Exam Board: OCR A-Level 2.4 - Types of Programming Language Specification: Computer Science H446 Watch on YouTube : Programming Paradigms Procedural Language Little Man Computer Addressing Modes Object-Oriented Language Programming paradigms are different approaches to writing and structuring code to solve problems . The procedural paradigm focuses on step-by-step instructions and the use of functions to organise tasks . The assembly paradigm operates at a low level , giving direct control over hardware through processor-specific instructions . The object-oriented paradigm models programs around objects that combine data ( attributes ) and behaviour ( methods ), promoting modular and reusable design . Procedural Language A procedural programming language organises code into reusable blocks ( procedures or functions ), which perform specific tasks in a step-by-step manner . It focuses on a clear sequence of instructions that operate on data, often using variables , loops and conditionals . Examples include Python , C , Pascal and BASIC . These languages are commonly used for software development , data processing and teaching programming fundamentals as they emphasise logical structure and modular design . Assembly Language / Little Man Computer Assembly language is a low-level programming language that uses short , readable codes called mnemonics to represent machine-level instructions executed by the CPU . Each command in assembly corresponds closely to a specific hardware operation , making it highly efficient but difficult to write and maintain . It is mainly used for embedded systems , device drivers and performance-critical tasks where direct control of hardware is required . For the OCR A-Level course , you must understand and be able to write code using the 11 mnemonics of Little Man Computer ( LMC ), which is an educational form of assembly language . Modes of Addressing Memory An addressing mode in assembly language defines how the CPU should locate the data (operand ) needed for an instruction (opcode ). It tells the processor whether the data is stored directly in the instruction , in memory , or needs to be calculated using an address or register . There are four main types : Immediate addressing : The operand contains the actual data to be used , rather than a memory address. Direct addressing : The operand contains the memory address where the required data is stored . Indirect addressing : The operand contains an address that points to another memory location holding the actual data . Indexed addressing : The operand provides a base address that is adjusted by the value in an index register to find the final memory address of the data . Object-Oriented Language An object-oriented programming ( OOP ) language organises code around objects , which combine data ( attributes ) and behaviour ( methods ) into reusable units . Key features of OOP : Classes are templates from which objects are created . Classes define both attributes (data ) and methods (functions or behaviours ). Encapsulation allows data to be protected by making attributes private and providing controlled access through public methods . Inheritance enables a class to reuse or extend the attributes and methods of a parent class , promoting the reuse of code . Polymorphism allows methods or attributes to behave differently depending on the object or class that uses them . Examples of OOP languages include Java , Python , C++ and C# . These languages are widely used for large-scale software development , game development and graphical user interfaces , where modularity and code reuse are crucial . Programming Paradigms Q uesto's K ey T erms Programming Paradigms: procedural language, assembly language, object-oriented language Procedural Language: input, output, comments, variables, casting, count-controlled iteration, condition-controlled iteration, logical operators, selection, string handling, subroutines, arrays, files Assembly Language: Little Man Computer, INP, OUT, LDA, STA, ADD, SUB, HLT, DAT, BRA, BRP, BRZ Modes of Addressing Memory: immediate, direct, indirect, indexed, index register, opcode, operand Object-Oriented Language: class, method, attribute, encapsulation, inheritance, polymorphism, instantiation, constructor method, get method, set method D id Y ou K now? Python was named after the 1970s British comedy group ' Monty Python ', not the snake . Guido van Rossum created Python in the late 1980s during his Christmas holidays as a ' hobby project '. 2.3 - Software Development A-Level Topics 3.1 - Compression & Encryption

Learn about project planning tools such as the Arrow diagram, Critical Path Analysis (CPA)/Critical Path Method (CPM), Flowcharts, Gantt charts, PERT charts and SWOT (Strengths / Weaknesses / Opportunities / Threats) analysis. 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) 3.2 - Project Planning Tools Watch on YouTube : Project planning tools Arrow diagram Critical path analysis Flowcharts Gantt charts PERT charts SWOT analysis Project Planning Tools Project planning tools help to visualise the project by clearly showing tasks , timelines and dependencies . They also break down complex work into smaller , manageable steps and can be used to track progress and identify delays . Each tool suits different project needs and has its own advantages and disadvantages . Choosing the right tool makes planning more accurate , efficient and successful . Arrow Diagram The arrow diagram method is a project planning tool that represents tasks as arrows connected in sequence to show their order and dependencies . It helps identify the critical path . This is the longest sequence of dependent tasks that determines the project’s minimum completion time . This method is useful for visualising task relationships , spotting bottlenecks and showing the order of activities . Critical Path Analysis Critical path analysis ( CPA ), also known as the critical path method ( CPM ), is a project planning tool used to identify the critical path . This is the sequence of tasks that determines the shortest possible project duration . It highlights tasks that cannot be delayed without affecting the overall timeline . Critical path analysis helps prioritise resources , manage dependencies and minimise project delays . Flowcharts A flowchart is a diagram that represents a process or workflow using standard symbols and arrows to show the sequence of steps . It helps visualise decision points and actions and clearly highlights the flow of information or tasks . Flowcharts make complex processes easier to understand , communicate ideas to clients and troubleshoot potential problems . Gantt Charts A Gantt chart is a visual project management tool that displays tasks along a timeline , showing their start and end dates . It helps track task dependencies , overlaps and progress at a glance . Gantt charts are useful for coordinating work , meeting deadlines and ensuring all project stages are completed in order . PERT Charts A PERT ( program evaluation and review technique ) chart is a project planning tool that maps tasks , their dependencies and timelines in a network diagram . It uses three time estimates ( optimistic , most likely and pessimistic ) to calculate expected completion times for each task . PERT charts are especially useful for scheduling complex projects and identifying the critical path to meet deadlines . SWOT Analysis SWOT analysis is a strategic planning tool used to identify a project’s strengths , weaknesses , opportunities and threats . Strengths and weaknesses focus on internal factors ( controllable by the organisation ), while opportunities and threats look at external influences ( outside of the organisation's control ). It helps guide decision-making by highlighting advantages , weaknesses to address and potential risks or openings in the wider environment . Q uesto's Q uestions 3.2 - Project Planning Tools: 1. Define the term 'critical path ' and explain why it is calculated . [3 ] 2. Explain the S , W , O and T in SWOT analysis (not just what they stand for). [4 ] 3. Choose three project planning tools and describe the advantages and disadvantages of each . [ 12 ] Henry Gantt , an American engineer , created the Gantt chart in the 1910s . It has been used as a planning tool in many major projects , including building the Hoover Dam . D id Y ou K now? 3.1 - Planning Projects Topic List 4.1 - Gathering Client Requirements

Learn how to split, edit and removes lines using files in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. Python 10c - REMOVE & Edit LINES Splitting a File The split command is used to split up a line of a file into different parts . The character or string in brackets after the split command is the value that will denote each split . In the example below I have split the file at each comma . Remember that Python numbering starts at 0 so the first section is 0, not 1. 0 1 2 3 The program below splits each line of the file at each forward-slash ( / ). The printed statement is the employee's first name, surname and job position. 0 1 2 3 4 Practice Task 1 Create a file (new txt document in Notepad) called movies. Type in the movie name, main actor, genre (e.g. horror), year it was released and your rating out of 10. Print just the movie name and year it released. Example solution: Deleting Lines in a File Exact Line Name The code below shows how to remove a line from a file using the exact name of the line , which will only work for short or simple files . First open the file in read move to save each line in a variable I've named lines. Then ask the user to input the exact line they want to remove (e.g. 'plum' in my example). Then open the file in write mode and use a for loop to read each line and only write it back into the file if it isn't equal to the line the user entered - such as 'plum'. The line.rstrip() command is important as it removes any spaces or empty lines that may interfere with matching the line to the input. Deleting Lines in a File Word in the Line The code below shows how to remove a line from a file if a certain word appears in that line , although this could be dangerous with large files. In my example I have written apple which has also removed pineapple! The difference from the previous program is to change the for loop so that it checks if the inputted word appears in the line . If it does appear then nothing happens (except a print statement to acknowledge it's been found). If the word doesn't appear then that line can be safely rewritten to the file . Practice Task 2 Download the trees text file. Give the user a choice of removing a specific tree or a type of tree. If they choose a specific tree then remove the line if it is an exact match (e.g. Field Maple). If they choose to remove a type of tree remove all lines that contain the name of that tree (e.g. willow) Make sure you actually check the file to see if the lines have been removed correctly! Example solution: Download the trees file: Sorting a File Sorting a file into alphabetical (or numerical ) order is a simple process. Open the file in read mode and save the lines into a list . The sort c ommand will automatically order the list of lines. If necessary, in the brackets type reverse = True to sort the list in reverse. Practice Task 3 Expand on your tree program from the previous practice task. As well as SPECIFIC or TYPE, allow the user to enter SORT to sort the tree file either in alphabetical order or reverse alphabetical order. Check the text file to see if it has been sorted correctly. You may make this a separate program from task 2 if you wish. Example solution: Editing Lines in a File Overwriting data in a file is a tricky process. The program below uses the same Employees.txt file as above but allows the user to change the address of an employee . A temporary file is created to store the lines of the employee file, but the line with the changes is replaced specifically with the new address. I have explained each line of the program to the right: When I executed the program below I entered Thomas Wynne's details and changed his address. When I opened the employees file the address had been updated : 1: Importing os allows me to rename and remove files later in the program. 3: Opens the employee file in read mode . 5 - 8: Input lines allow the user to enter the first name, surname and the person's new address. 10: A found flag is set up and set to False . 12: The for loop cycles through each line in the file. 13: Each line is split into separate parts from each / . 15: An if statement checks if the first name and surname match an employee in the file. 16: A replacement line is created by putting the original line together but with the new address. 18: The found flag is changed to True because the employee first name and surname matched . 19: A temporary file is created and opened in write mode . 20: The seek command restarts the file at line 0 . 22: The for loop cycles through each line of the employee file from the beginning. If the first name and surname match it will write the new line to the file, otherwise it will rewrite the original line . 28 & 29: Both files are closed . 31 & 32: If the names didn't match , an appropriate message is printed. 34 - 37: If the address was changed, the original file is renamed and deleted and the temp file is renamed as the original file. Practice Task 4 Use the movie file you created for practice task 1. Ask the user to enter the name of a movie. Ask them to enter an updated rating out of 10. Update the file to change the rating to the new value. Example solution: ⬅ 10b - Read & Search Files Section 10 Practice Tasks ➡

Learn about different types computers such a desktops, games consoles, laptops, smart speakers, smart TVs, smartphones, tablets, augmented reality (AR), virtual reality (VR) and mixed reality (MR) devices. Based on Unit F160 (Fundamentals of Application Development) for the OCR Cambridge Advanced National in Computing (H029 / H129) (AAQ - Alternative Academic Qualification). Qualification: Cambridge Advanced National in Computing (AAQ) Unit: F160: Fundamentals of Application Development Certificate: Computing: Application Development (H029 / H129) 5.1.2 - Types of Device Watch on YouTube : Types of Device Applications can be developed for a range of different devices , each type of device having its own characteristics and common uses . The characteristics of popular devices, such as laptop and tablets , may be well known, but ensure you know the difference between augmented reality ( AR ), virtual reality ( VR ) and mixed reality ( MR ) devices. Types of Device Common Devices Desktops are powerful and customisable personal computers designed for use at a desk . Game consoles are designed specifically for playing video games , usually connected to a TV . Laptops are portable computers with a built-in screen and keyboard , suitable for work on the go . Smart speakers are voice-controlled devices that play music , answer questions and can control smart home gadgets . Smart TVs have internet access , interactive features and apps for streaming and browsing . Smartphones have internet , GPS and Bluetooth connectivity , apps and communication functions . Tablets use a touchscreen larger than a phone, they are more portable than a laptop and good for browsing and media . Augmented Reality (AR ) is technology that overlays digital images or information onto the real world . Virtual Reality (VR ) uses a computer-generated 3D environment that fully immerses the user , usually with a headset . Mixed Reality (MR ) is a blend of AR and VR where digital objects interact with the real world in real time . Q uesto's Q uestions 5.1.2 - Types of Device: 1. Explain the difference between the three types of 'reality ' devices . [3 ] 2. Justify which devices a streaming service should consider for an app . [4 ] 3. Describe the characteristics of any devices not covered in your responses to Q1 and Q2 . [ 5 ] The AR app Pokémon Go was so popular when it released in 2016 that within the first 6 months players had walked a combined 8.7 billion kilometres ( 200,000 trips around the Earth ). D id Y ou K now? 5.1.1 - Human-Computer Inter. Topic List 5.2 - Visual Design Considerations

Learn 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