The fourth part of a quick guide to the basics of Python aimed at Key Stage 3 students. Learn about calculations and simple mathematical operators. Python - #4 - Calculations 1. Creating Calculations To add in Python use + To subtract in Python use - To multiply in Python use * To divide in Python use / Task 1 - Create a new Python program and save the file as 4-Calculations.py Print 4 different calculations - use each operator once.(add/subtract/multiply/divide) Python is very clever, so don't be afraid to make your own calculations using larger numbers and more than one operator . 2. Using Inputs and Calculations You can ask the user to enter numbers by writing input lines. Python can then perform calculations using the numbers that the user has entered. Don't forget to add int ( and double close brackets when using numbers ! Task 2 - Copy the new code from the picture. Change the text and num1 so you are dividing by 5 not 3. Don't delete your earlier code , just add this underneath. I have cropped the images to make the new code clearer. 3. Using Calculations in a Sentence When we have printed the calculations so far, they have not been very informative! You can print calculations together with sentences so that they mean more. Use a comma ( , ) between calculations and sentences . Task 3 - Use the pictures to help you add commas and sentences to your program to be more informative. Challenge Programs Use everything that you have learned on this page to help you create these programs... Challenge Task 1 - Multiplication Create a new Python program. Save it as ' 4 -Multiplication.py ' Add a comment at the top with your name and the date. Write an input line ( don't forget int ! ) that asks the user to enter number 1. Write an input line ( don't forget int ! ) that asks the user to enter number 2. Multiply number 1 and number 2 together and print the answer. BONUS : Try to show number 1 and number 2 in the print statement (see practice task 3 to help you). Remember: Break up variables in a print line by using commas. When you run it, it could look something like this: Challenge Task 2 - Retirement Create a new Python program. Save is as ' 4-Retirement.py ' Add a comment at the top with your name and the date. Write an input line ( don't forget int ! ) that asks the user to enter their age. Print the year that they will turn 65. (This is slightly tricky. Hint : You need to know their age, and you need to know the current year. You need to subtract something, and you need to add something. Try using scrap paper to help you figure it out.) 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: <<< #3 Inputs #5 Selection >>>

Learn about internet topics including web browsers, URL structure and DNS servers. Based on the 2020 Eduqas (WJEC) GCSE specification. 3.7: The Internet Exam Board: Eduqas Specification: 2020 What is the internet? The internet is a global network of interconnected networks . The world wide web (WWW ) is not the same as the internet. It is a way of accessing information , using protocols such as HTTPS to view web pages . What is a web browser? A web browser is software that uses the HTTP or HTTPS protocol to access and display web pages . Popular web browsers include Google Chrome , Mozilla Firefox and Microsoft Edge . What is a URL? URL stands for Uniform Resource Locator . Web pages are accessed by typing a URL (a web address) into the address bar of a web browser . The URL is the complete address that matches an IP address where the website is stored. We use URLs because they are easier to remember than IP addresses, for example, 'twitter.com' is simpler than '199.59.149.165'. What is the structure of a URL? A URL is structured into different segments: What is a DNS Server? A DNS ( Domain Name System ) server stores a list of domain names and a list of corresponding IP addresses where the website is stored. The first thing to understand is that every web page has a domain name that is easy for humans to remember and type in (such as www.csnewbs.com ) as well as a related IP address (such as 65.14.202.32) which is a unique address for the device that the web page is stored on. The steps taken to display a web page: 1. A domain name is typed into the address bar of a browser . 2. The browser checks a local (cached) host file to check if it already holds the IP address, but if it doesn't... 3. A query is sent to the local DNS server for the corresponding IP address of the domain name . www.facebook.com 4. The local DNS server will check if it holds an IP address corresponding to that domain name. If it does it passes the IP address to your browser . 66.220.144.0 5. The browser then connects to the IP address of the server and accesses the web site . If the local DNS server does not hold the IP address then the query is passed to another DNS server at a higher level until the IP address is resolved. If the IP address is found, the address is passed on to DNS servers lower in the hierarchy until it is passed to your local DNS server and then to your browser. Q uesto's Q uestions 3.7 - The Internet: 1a. Describe the difference between the internet and the world wide web ( WWW ). [ 2 ] 1b. What is the purpose of a web browser ? [ 2 ] 1c. Why do humans use URLs instead of IP addresses? [ 1 ] 1d. Write out the following URL and label each section: https://www.skynews.co.uk/worldnews/ukstockmarket [ 6 ] 2a. What is a DNS server ? [ 2 ] 2b. Describe, using a mix of text and icons / images , how a DNS server is used to display a web page . [5 ] 2c. Describe how a DNS server searches for an IP address if it is not found on the local DNS server . [ 2 ] 3.6 - 7-Layer OSI Model Theory Topics 3.8 - Cyber Threats

Learn about how to convert between the denary (decimal), binary and hexadecimal number systems. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). Exam Board: OCR 2.4a: Number Systems Specification: J277 Watch on YouTube : Binary and Denary Hexadecimal Number System Ranges Binary to Denary Denary to Binary Binary to Hexadecimal Hexadecimal to Binary Denary to Hexadecimal Hexadecimal to Denary What is binary? By now you should know that computer systems process data and communicate entirely in binary . Topic 2.3 explained different binary storage units such as bits (a single 0 or 1), nibbles (4 bits) and bytes (8 bits). Binary is a base 2 number system. This means that it only has 2 possible values - 0 or 1 . What is denary? Denary (also known as decimal ) is the number system that you've been using since primary school. Denary is a base 10 number system. This means that it has 10 possible values - 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 . Binary & Denary Convert from binary to denary: Convert from denary to binary: Hexadecimal What is hexadecimal? Hexadecimal is a base 16 number system. This means that it has 16 possible values - 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E and F . Hexadecimal is used as a shorthand for binary because it uses fewer characters to write the same value . This makes hexadecimal less prone to errors when reading or writing it , compared to binary. For example, 100111101011 in binary is 9EB in hexadecimal. Hexadecimal only uses single-character values. Double-digit numbers are converted into letters - use the table on the right to help you understand. Binary to hexadecimal: Hexadecimal to binary: Converting from denary to hexadecimal / hexadecimal to denary To convert from denary to hexadecimal or from hexadecimal to denary , it is easiest to convert to binary first . However, it is possible to convert directly from denary to hexadecimal or directly from hexadecimal to denary . The videos below explain both methods . Denary to hexadecimal: Hexadecimal to denary: Watch on YouTube Watch on YouTube Watch on YouTube Watch on YouTube Watch on YouTube Watch on YouTube Q uesto's Q uestions 2.4a - Number Systems: 1. Explain why hexadecimal numbers are used as an alternative to binary . Use an example . [ 3 ] 2. Convert the following values from binary to denary : a. 00101010 b. 11011011 c. 01011101 d. 11101110 e. 01011111 [1 each ] 3. Convert the following values from denary to binary : a. 35 b. 79 c. 101 d. 203 e. 250 [1 each ] 4. Convert the following values from binary to hexadecimal : a. 11110101 b. 01100111 c. 10111010 d. 10010000 e. 11101001 [1 each ] 5. Convert the following values from hexadecimal to binary : a. C2 b. 8A c. DE d. 54 e. F7 [1 each ] 6. Convert the following values from denary to hexadecimal : a. 134 b. 201 c. 57 d. 224 e. 101 [1 each ] 7. Convert the following values from hexadecimal to denary : a. 32 b. A5 c. 88 d. C0 e. BE [1 each ] Click the banners below to try self-marking quizzes (Google Forms) on these topics. Binary to Denary: Denary to Binary: Binary to Hexadecimal: Hexadecimal to Binary: 2.3 - Data Units Theory Topics 2.4b - Binary Addition & Shifts

Learn about the denary, binary and hexadecimal number systems and how to convert between them. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification. 1.8 & 1.9 - Number Systems & Conversion Exam Board: OCR Specification: 2016 - Unit 1 What is binary? What is denary? Denary (also known as decimal ) is the number system that you've been using since primary school. Denary is a base 10 number system. This means that it has 10 possible values - 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 . How to convert from binary to denary: How to convert from denary to binary: What is hexadecimal? Hexadecimal is a base 16 number system. This means that it has 16 possible values - 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E and F . Hexadecimal is used as a shorthand for binary because it uses fewer characters to write the same value . This makes hexadecimal less prone to errors when reading or writing it , compared to binary. For example, 100111101011 is 9EB. Hexadecimal only uses single-character values. Double-digit numbers are converted into letters - use the table on the right to help you understand. How to convert from binary to hexadecimal: How to convert from hexadecimal to binary: Converting from denary to hexadecimal / hexadecimal to denary To convert from denary to hexadecimal or the other way round you must convert to binary first . Denary > Binary > Hexadecimal Hexadecimal > Binary > Denary Use the videos on this page if you need help converting to or from binary. The most common number systems question in exams are from denary to hexadecimal or from hexadecimal to denary so make sure that you practice these conversions. Q uesto's Q uestions 1.8 & 1.9 - Number Systems: 1. Explain why hexadecimal numbers are used as an alternative to binary . [ 2 ] 2. Convert the following values from binary to denary : a. 00101010 b. 11011011 c. 01011101 d. 11101110 e. 01011111 [1 each ] 3. Convert the following values from denary to binary : a. 35 b. 79 c. 101 d. 203 e. 250 [1 each ] 4. Convert the following values from binary to hexadecimal : a. 11110101 b. 01100111 c. 10111010 d. 10010000 e. 11101001 [1 each ] 5. Convert the following values from hexadecimal to binary : a. C2 b. 8A c. DE d. 54 e. F7 [1 each ] 6. Convert the following values from denary to hexadecimal : a. 134 b. 201 c. 57 d. 224 e. 101 [1 each ] 7. Convert the following values from hexadecimal to denary : a. 32 b. A5 c. 88 d. C0 e. BE [1 each ] Watch on YouTube Watch on YouTube Watch on YouTube Watch on YouTube By now you should know that computer systems process data and communicate entirely in binary . Section 1.7 explained different binary storage units such as bits (a single 0 or 1), nibbles (4 bits) and bytes (8 bits). Binary is a base 2 number system. This means that it only has 2 possible values - 0 or 1 . Click the banners above to try self-marking quizzes (Google Form) on these topics. Denary to Binary: Binary to Denary: Binary to Hexadecimal: Hexadecimal to Binary: 1.7 - Units of Measurement Topic List 2.1 Software Types

The list of topics in the 2020 Eduqas (part of WJEC) GCSE Computer Science specification. Eduqas GCSE Computer Science These pages are based on the Eduqas GCSE Computer Science 2020 specification . 1. Hardware 1.1 - The Central Processing Unit (CPU) 1.2 - The FDE Cycle 1.3 - Primary Storage 1.4 - Secondary Storage 1.5 - Performance 1.6 - Additional Hardware 2. Logical Operators & Boolean 2.1 - Logical Operators 2.2 - Boolean Algebra 3. Networks & Security 3.1 - Network Characteristics 3.2 - Data Packets & Switching 3.3 - Network Topology 3.4 - Network Hardware & Routing 3.5 - Protocols 3.6 - 7-Layer OSI Model 3.7 - The Internet 3.8 - Cyber Threats 3.9 - Protection Against Threats 4. Data 4.1 - Number Systems 4.2 - Signed Binary 4.3 - Binary Calculations 4.4 - Arithmetic Shift 4.5 - Character Sets & Data Types 4.6 - Graphical Representation 4.7 - Sound Representation 4.8 - Compression 5. Data Organisation 5.1 - Data Structures & File Design 6. Operating Systems 6.1 - Operating Systems 6.2 - Utility Software 7. Principles of Programming 7.1 - Language Levels 8. Algorithms & Constructs 8.1 - Programming Principles 8.2 - Understanding Algorithms 8.3 - Writing Algorithms 8.4 - Sorting & Searching Algorithms 8.5 - Validation & Verification 9. Software Development 9.1 - IDE Tools 10. Program Construction 10.1 - Translators 10.2 - Stages of Compilation 10.3 - Programming Errors 11. Technological Issues 11.1 - Impacts of Technology 11.2 - Legislation Component 2 (Programming Exam) Python

Learn how to use time commands to display the current date and time in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 5c - Time & Date ctime() The easiest way to output the current time and date is to use the ctime() command. Import the ctime command from the time library before you use and print it: from time import ctime print ( "Current time:" , ctime()) = Current time: Wed Sep 13 16:07:20 2023 This will print the time and date, but it looks rather unprofessional, and the exact format depends on the type of system that you are currently running so it may vary for different users. Date / Time Task 1 ( Dentist Surgery) Print a greeting for a dentist surgery with the current date and time. Example solution: Welcome to Greenvale Dentist Surgery, it is currently: Wed Sep 13 16:16:24 2023 strftime() A better alternative to the ctime() command is to use strftime() which stands for str ing f rom time as you can select specific parts of the date and time to display. This command requires a directive to be written with a percentage symbol as a string in the brackets . For example, the current hour (%H ), minute (%M ) and second (%S ) can be printed between colons to show the time . from time import strftime print ( "The current time is" , strftime( "%H:%M:%S" )) = The current time is 13:18:57 There are many different directives that you can use to display exactly what you are looking for, such as: from time import strftime day = strftime( "%A" ) print ( "The current day is" , day) month = strftime( "%B" ) print ( "The current month is" , month) year = strftime( "%Y" ) print ( "The current year is" , year) = The current day is Thursday The current month is September The current year is 2023 The following directives can be used with strftime(). Don't forget that directives must be typed within speech marks . Date - Weekday: %a – Current day of the week abbreviated (e.g. Sun, Mon) %A – Current day of the week in full (e.g. Sunday, Monday) %w – Current day of the week in chronological order (0 is Sunday and 6 is Saturday) %W – Current week number (e.g. 01, 26, 52) Month: %d – Current day of the month (e.g. 01, 11, 31) %m – Current month as a number (e.g. 01, 06, 12) %b – Current month abbreviated (e.g. Jan, Jun, Dec) %B – Current month in full (e.g. January, December) Year: %y – Current year abbreviated (e.g. 16, 17) %Y – Current year in full (e.g. 2016, 2017) %j – Current day of the year (e.g. 001, 150, 365) Time - Hour: %H – Current hour in 24-hour clock (e.g. 00, 12, 20) %I – Current hour in 12-hour clock (e.g. 01, 08, 12) %p – Whether it is currently AM or PM Minute: %M – Current minute (e.g. 00, 30, 59) Second: %S – Current second (e.g. 00, 30, 59) More Directives - %z – Current time difference from UTC (Co-ordinated Universal Time) (e.g. +0000, -0500, +1100) %Z – Current time zone (e.g. GMT Standard Time, EST, CST) Just looking for a quick date or time display and not bothered about customisation? Try these: %c – Current date and time in full (e.g. Tue Feb 19 13:35:20 2016) %x – Current date (e.g. 19/02/16) %X – Current time (13:36:20) Date / Time Task 2 ( Calendar App ) Create a program that asks the user if they want to see the current date , the current time or 'other '. Use the strfftime directives above to show what the user asks for. It's up to you which directives you use for the 'other' option , such as displaying the current day of the year (%j ) or current week of the year (%W ). Example solutions: Type TIME for the current time, DATE for the current date or OTHER: TIME The current time is 13:46PM Type TIME for the current time, DATE for the current date or OTHER: DATE The date today is Thursday 14 September 2023 Type TIME for the current time, DATE for the current date or OTHER: OTHER Did you know today is day number 257 of 2023? Between Dates You may want to work out the number of days between two dates . This can be done by importing the date command from the timedate library. Below is a simple example: from datetime import date date1 = date(2021,9,15) date2 = date(2022,1,20) difference = date2 - date1 print ( "There are" , difference.days , "days between" , date1 , "and" , date2) Make sure the date is entered in the format of year, month, day . The .days code removes the difference in hours and seconds to just display the number of days difference. There are 127 days between 2021-09-15 and 2022-01-20 Today's Date The program here uses strftime to check the current year, month and day and organise it into the date format . This can then be used together with code similar to the program above to check the number of days between one specific date and the current date. from datetime import date from time import strftime thisyear = int (strftime( "%Y" )) thismonth = int (strftime( "%m" )) thisday = int (strftime( "%d" )) todaysdate = date(thisyear,thismonth,thisday) print ( "The date today is" , todaysdate ) The date today is 2023-09-14 Input a Date The program here shows how to input a date into a format that can then be used by Python to work out the difference between two dates . from datetime import date year = int ( input ( "Enter a year: " ) month = int ( input ( "Enter a month: " ) day = int ( input ( "Enter a day: " ) chosendate = date(year,month,day) print ( "The chosen date is" , chosendate ) Enter a year: 1964 Enter a month: 5 Enter a day: 13 The chosen date is 1964-05-13 Date / Time Task 3 ( Days Alive) Create a program that works out how long the user has been alive for . Use the examples above to automatically make today's date and then allow the user to input their year , month and day of birth. Get Python to work out the difference between today and their date of birth. Example solutions: Enter a year: 1998 Enter a month: 3 Enter a day: 29 You have been alive for 9300 days! Enter a year: 2007 Enter a month: 12 Enter a day: 25 You have been alive for 5742 days! ⬅ 5b - Sleep 5d - Colorama ➡

Learn about the motherboard, graphics processing unit (GPU), sound card, embedded systems and input / output systems. Based on the 2020 Eduqas (WJEC) GCSE specification. 1.6: Additional Hardware Exam Board: Eduqas Specification: 2020 1.6a - Internal Hardware Motherboard The motherboard is the main circuit board of a computer , unique for each device. It holds and connects the different components together , allowing data to be transferred between them. Components such as the CPU and ROM are directly attached to the motherboard. The motherboard has expansion slots for additional cards (i.e. sound cards) and ports (i.e. USB). Graphics Processing Unit (GPU) Sound Card A GPU is a microprocessor that performs complex calculations to generate graphical images to be displayed on a monitor . There are two types of GPU, integrated GPUs within the motherboard circuitry or dedicated GPUs on an additional card (known as a 'graphics card'). An integrated GPU is cheaper and generates less power because it uses the RAM of the computer . Integrated GPUs are used in tablets and laptops as they generate less heat and are optimal for general computing uses (e.g. web browsing or watching movies). A dedicated GPU is more expensive and generates more heat, often requiring a fan because it contains its own memory . Dedicated cards are used by animation professionals and professional gamers who require the best graphics. Sound cards convert analogue sound waves into digital data (binary) when inputting audio through a microphone. 0010 1011 0101 0101 0110 0111 0101 0001 0101 0010 1011 0101 0101 0110 0111 0101 0001 0101 Sound cards also convert digital data (binary) into analogue sound waves to output audio through speakers or headphones. 1.6b - Embedded Systems Example: A washing machine has a control chip that manages the different program cycles. An embedded system is a computer system built into a larger machine to provide a means of control . Embedded systems perform a specific pre-programmed task which is stored in ROM . An embedded system uses a combination of hardware and software . Example: A traffic light has a control chip that determines when to change to a green or red light. 1.6c - Input & Output Devices Input devices are used by humans to interact with a computer system , through methods such as text , voice or touch . Output devices show the result of computer processing , such as sound , printed text or a visual display on a monitor. Storage devices , such as a USB stick or an external hard drive, are neither input nor output devices - see 1.4 . Input Devices These are just some of the more common input devices . A mouse and a keyboard have been described in further detail. Are there any devices below you haven't heard of before? Mouse Benefits: Easy to navigate a graphical user interface. A wireless mouse takes up less space . Faster to select options (e.g. in a video game). Drawbacks: Difficult to use for people with restricted hand movement . Difficult to use on some surfaces . Other input devices: Scanner Controller Microphone Webcam Chip Reader OCR Scanner OMR Scanner Barcode Scanner Graphics Tablet Sensors (e.g. light or temperature) Touch Screen Remote Control Biometric Scanner (e.g. fingerprint or iris) Concept Keyboard Sip / Puff Switch Keyboard Benefits: Quick to input text . Easy to use with a familiar layout on most keyboards. Keys can be customised and shortcuts can be used . Drawbacks: Takes up a large amount of space on a desk. Difficult for people to use with restricted hand movement or poor eyesight . Output Devices Monitor These are just some of the more common output devices . A monitor and a printer have been described in further detail. Are there any devices below you haven't heard of before? Other output devices: Plotter Speakers Projector Alarm Light Headphones Touch Screen Braille Terminal What is it? A monitor is required to see the result of human input and computer processing . Monitors can be bought in different sizes and resolutions for a range of purposes such as video editing or playing games . Monitors settings can be changed to alter the brightness or contrast . Printer What is it? A printer uses ink or toner to print a document (such as text or images) onto paper . Inkjet printers use ink cartridges , are generally slower and print in a lower quality . Laser printers use toner cartridges and are generally quicker and print to a higher quality . Q uesto's Q uestions 1.6 - Additional Hardware: 1.6a - Internal Hardware 1. What is the purpose of the motherboard ? [2 ] 2a. What is the purpose of the GPU ? [ 2 ] 2b. Describe two differences between integrated and dedicated expansion cards . [ 4 ] 3. Explain how a sound card works. [ 4 ] 1.6b - Embedded Systems 1. What is an embedded system ? [3 ] 2a. Give two examples of an embedded system. [ 2 ] 2b. Research and describe another example of an embedded system. [ 2 ] 1.6c - Input & Out[ut Devices 1. Choose four input devices and describe at least two benefits and two drawbacks of using each one. [ 8 ] 2. Describe three output devices . [ 3 ] 3. Justify which input and output devices would be most suitable in the following scenarios: a. A teacher needs to take the class register . [ 4 ] b. A family want to communicate with their cousins in Australia. [ 4 ] c. The school movie club wants to play Star Wars in the assembly hall. [ 4 ] d. An e-sports player is taking part in an online multiplayer tournament . [ 4 ] e. A laboratory needs security so that only registered scientists can enter. [ 4 ] 1.5 - Performance 2.1 - Logical Operators Theory Topics

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 about different formats for presenting data on the internet including webpages, blogs, streamed video and audio, document stores and RSS feeds. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification for Unit 2 (Global Information). 1.6 - Information Formats Exam Board: OCR Specification: 2016 - Unit 2 The following formats are used to display information on the internet . Web Pages Web pages can be used for a diverse range of purposes including advertising products, reporting information , displaying images and eCommerce (online shopping). There are two types of web page: Static web page Static web pages contain content that is pre-built and remains the same each time the page is loaded . Static web pages are cheaper and easier to create and load quicker ; they use basic HTML. It can be changed by the site editor but will appear the same for everyone who has access to it, such as a classic promotional website for a small company. Dynamic web page Dynamic web pages are generated when they are loaded and can appear different to different users . Dynamic web pages are harder to code but they can be linked to databases to allow them to show personalised content to whoever is viewing the site; they are written in server-side languages like PHP. The Amazon homepage is an example of a dynamic web page as personalised deals based on previous user history will be shown if you are logged in with an account. Blogs Blogs are used to share information with like-minded individuals, such as those who enjoy the same hobbies or beliefs . Charities , game developers and other businesses also use blogs as a way of updating their customer base with what they have done or what they are working on. Blogs can feature multimedia such as text, images, videos and links to other sites. Advantages of Blogs Disadvantages of Blogs ✓ Share information with followers in the format of text, images and video . ✓ Blogs and vlogs can unite people with similar interests , such as a cookery blog or travel vlog. X Takes a lot of effort and time to create posts, especially if videos need to be edited before posting. Potential customers could be lost if blogs aren't updated regularly . X It can be difficult to build up a customer base directly from a blog. Posts must be engaging , researched and correct . Podcasts A podcast is a downloadable audio file , usually on a certain topic such as sports or gaming that can be listened to when convenient for the user. Spotify and Apple Music have a wide library of podcasts. Advantages of Podcasts Disadvantages of Podcasts ✓ Podcasts are not (usually) recorded live , so they can be edited and uploaded at a certain time each week. ✓ Podcasts can be listened to when convenient for the user, so they can't 'miss' it and can catch up when is best for them. ✓ Podcasts are becoming more and more popular , so the possible audience base is growing each year. Celebrity guests are one way to entice more listeners. X Takes time to record a podcast, especially if they need to be edited to add in music or sound effects or to remove mistakes . X It can be difficult to build up an audience directly from a podcast. Podcasts should be on a topic that interests people and spoken in an engaging way. Streamed Audio & Video Streaming is the process of receiving video / audio data in a continuous flow . This allows the user to access the video / audio immediately , without having to wait for the file to download entirely. For example, the BBC provide live radio streaming online for their radio shows and BBC iPlayer allows users to watch 'catch up' programs that previously aired. YouTube is a widely-used streamed video platform and Spotify is a popular streamed audio service. Advantages of Streamed Media Disadvantages of Streamed Media ✓ Streaming does not require data to be downloaded entirely before use - users can watch / listen as soon as the connection starts . ✓ Streaming is harder for users to share than downloading a file . Netflix uses this as a form of piracy protection . X Streaming requires high bandwidth so users may suffer performance issues on slower devices and networks . X Streaming requires a constant network connection compared to downloadable media which can be used when offline / outside. Social Media Channels Social media channels provide a huge amount of data on users in an informal space. Organisations can receive feedback through user posts and comments . Real-time statistics like views, likes and shares provide an insight to user opinion . Social media channels include traditional sites such as Facebook and Twitter as well as business and recruitment platforms such as LinkedIn . Discussion boards and forums , such as Reddit , are increasingly popular for users to discuss similar hobbies and interests such as politics, gaming and healthy eating. Advantages of Social Media Disadvantages of Social Media ✓ Social media can increase a business' online presence as it is online 24/7 for users to comment and interact with posts. ✓ Posts can be shared between users and their contacts, allowing a post to 'go viral' and be seen by potentially millions of viewers . ✓ Posts can be shared in different information styles such as text , images , video or hyperlinks to other websites. ✓ Businesses can use social media to communicate with their customer s , such as direct messages on Facebook if a customer is unhappy. X Businesses may need to hire a social media manager to interact with customers , update posts and remove spam. X Negative posts can be shared and spread very quickly , such as if a customer complains about how a business treated them poorly. X Businesses must be cautious about what they post , to not accidentally offend others and damage their reputation . Emails Emails can be used to provide information to a large amount of people almost instantly . A company may use an email to advertise new products , inform potential customers of a marketing promotion or target specific users based on previous interactions. Advantages of Emails Disadvantages of Emails ✓ Faster (almost instant) and cheaper (usually free) to send an email compared to traditional letters . ✓ Files can be attached to the email, such as images, videos or forms to complete. ✓ An audit trail can be kept, recording communication between the company and its customers. ✓ Emails can be sent, delivered and read at the user's convenience and to any internet-enabled device across the world . X An internet connection is required to open and read the email. Larger attachments may not open on mobile devices. X Malware can spread through email attachments. Phishers use emails to gain access to personal information and account details . X Some attachments sent via email may be unreadable on different devices / operating systems. X Emails may automatically go into the spam / junk folder and be deleted without being read . Document Stores Document stores allow users to store online files in cloud storage . Common services are Google Drive , Dropbox and Microsoft's OneDrive . Storing documents in the cloud allows users to edit and access them from any location with an internet connection and opens up opportunities for collaboration . Many organisations offer cloud storage space for free up to a certain amount before charging customers for more data. Document stores are very convenient for users and replace the need for portable storage devices like USB sticks. Teachers can use documents stores to share resources with other staff in a school . Documents stores can only be accessed with an internet connection so files will be unavailable during maintenance or network failure. Users rely on the cloud hosting provider, such as Microsoft and Google to keep the data secure and available . RSS Feeds RSS Feeds (short for Rich Site Summary ) allow users to subscribe to updates from their favourite websites. It is a web feed that updates whenever a subscribed site releases new information. For example, the BBC used to post updates for important news headlines which appeared in a subscribed user's RSS feed. As of 2020 most browsers no longer have built-in RSS functionality and it is rarely used . Q uesto's Q uestions 1.6 - Information Formats: 1. Describe the difference between static and dynamic web pages . [4 ] 2. For each type of information format describe its advantages and disadvantages . a. Blogs [8 ] b. Podcasts [8 ] c. Streamed Audio / Video [8 ] d. Social Media [8 ] e. Emails [8 ] 3. Explain how document stores could be used by organisations and individuals . [4 ] 4. Explain what an RSS feed is and how an organisation could use it . [3 ] 1.5 - WWW Technologies Topic List 1.7 & 1.8 - Internet Pros & Cons

Learn about operating systems, memory management (segmentation and paging), scheduling, interrupts, the BIOS, device drivers and virtual machines Based on the OCR H446 Computer Science A-Level specification. Exam Board: OCR A-Level 2.1 - Systems Software Specification: Computer Science H446 Watch on YouTube : Operating systems functions Paging & segmentation Interrupts Scheduling algorithms Types of operating system BIOS Device drivers Virtual machines This topic looks at how the operating system manages the resources of a computer system . It also includes programs related to the operating system , such as the BIOS , device drivers and virtual machines . Operating Systems The operating system performs essential functions to keep a computer running efficiently . It provides a user interface , such as a command line or graphical user interface ( GUI ), and ensures system security by managing access rights and protecting files . The OS manages hardware , coordinating devices like the CPU , printers and hard drives and provides built-in utilities for tasks such as file management and disk defragmentation . It acts as a platform for software , allowing applications to be installed and run . The OS also schedules jobs , handles interrupts from devices, and manages memory , ensuring each process has the resources it needs without conflicts. Paging & Segmentation Paging is a memory management method that splits memory into equal-sized blocks called pages . This makes memory use more efficient as programs don’t need to be stored in one continuous block but unused space may be wasted inside a page . Segmentation divides memory into segments of different sizes based on program structure . This makes it easier to organise parts of a program , but because segments are different sizes , it can leave small unused gaps in memory that can’t be easily filled by other data. Interrupts An interrupt is a signal that tells the CPU to pause its current task and respond to something more urgent . Interrupts can come from hardware , such as a keyboard press , or from software , such as an error . When an interrupt occurs , the CPU saves its current state by placing current register values into a stack . The CPU runs an interrupt service routine ( ISR ) to handle the interrupt event . After the ISR finishes , the CPU restores its state by popping values from the stack and continues the original program . Scheduling Scheduling algorithms are used by the CPU to decide the order in which processes are executed . They aim to manage CPU time efficiently and ensure all programs get a fair share of resources . Common scheduling algorithms include: First-Come First-Served : Processes are executed in the order they arrive to the CPU . Round Robin : Each process gets a fixed time slice in turn , cycling through all processes. Shortest Job First / Shortest Time Remaining : These methods identify the process with the shortest estimated runtime to be executed first . Multi-Level Feedback Queue : Uses multiple queues with different priority levels . Processes can be moved between queues to avoid starvation . Types of OS Different types of operating systems exist depending on the computer system and purpose : Multitasking OS : Allows a single computer to run multiple programs at the same time by quickly switching between them. Multi-user OS : Lets multiple users access the computer and its resources simultaneously , often via a network . Distributed OS : Manages a group of networked computers as a single system , sharing resources and tasks . Embedded OS : Designed for devices with specific functions , like microwaves or smart TVs , often with limited resources . Real-time OS : Provides immediate processing and responses for time-critical tasks , used in systems like medical devices or industrial robots . The BIOS The BIOS (Basic Input/Output System ) is firmware stored in ROM that helps the computer start up and manage initial communication between hardware and the operating system . During the start-up sequence , the BIOS first checks that essential hardware (e.g. the CPU and RAM ) is present and working correctly by running a Power-On Self Test (POST ). Signals are transmitted to all connected components . The BIOS then runs the bootstrap program to locate and load the operating system from a connected storage device into RAM . Once the OS is loaded , control is handed over to it, allowing the computer to become fully operational . Device Drivers A device driver is software that allows the operating system to communicate with hardware devices such as printers , graphics cards or keyboards . Hardware and the OS speak different ' languages ', so the driver translates OS instructions into commands the device can understand and vice versa. They are needed because, without drivers , the OS wouldn’t know how to control the hardware or use its features properly. Drivers also allow devices to work with different versions of an operating system and enable updates that improve performance or fix bugs . Virtual Machines A virtual machine is a software-based computer that runs an operating system and applications like a real computer , using part of the host computer’s hardware . It is isolated from the main system , so it can operate safely without affecting the host . Virtual machines are commonly used for testing software , running multiple operating systems and safely handling untrusted files . They provide flexibility , efficient hardware use and a secure environment for experimentation . Q uesto's K ey T erms Operating Systems: user interface, file management, user management Memory Management: paging, segmentation, virtual memory Interrupts: interrupt, interrupt service routine, stack Scheduling Algorithms: first come first serve, round robin, shortest job first, shortest time remaining, multilevel feedback queue Types of Operating System: multitasking, multi-user, distributed, embedded, real-time BIOS: ROM - power-on self-test (POST) Device Drivers: device driver Virtual Machines: virtual machine, thin clients, servers D id Y ou K now? New versions of the Android operating system used to be named alphabetically after sweet treats , from Cupcake , Donut and Eclair to Nougat , Oreo and Pie - the final named update in 2019 . 1.3 - Input, Output & Storage A-Level Topics 2.2 - Applications Generation

Learn about the different parts of computational thinking including thinking abstractly, ahead, procedurally, logically and concurrently. Based on the OCR H446 Computer Science A-Level specification. Exam Board: OCR A-Level Specification: Computer Science H446 1.1 - Computational Thinking Watch on YouTube : Thinking Abstractly Thinking Ahead Thinking Procedurally Thinking Logically Thinking Concurrently Computational thinking is the process of approaching and solving problems in a logical , systematic way (like a computer would ) using techniques such as abstraction , decomposition , pattern recognition and algorithmic thinking . There are five categories of computational thinking you need to know. Thinking Abstractly Abstraction is the process of removing unnecessary detail so that a problem can be represented more simply . It helps programmers focus on the essential features of a task, reducing complexity and making solutions easier to design , understand and maintain . When programming , abstraction can be applied by simplifying real-world systems into models that contain only the information needed for solving the problem . Because abstractions leave out certain details , they always differ from reality , and it is important to understand which elements have been included , which have been excluded and why . YouTube video uploading soon Thinking Ahead Programs often make use of inputs and outputs to receive data from the user or another system and then return results or feedback. Many programs rely on preconditions - rules or requirements that must be met before a function or procedure runs correctly - to prevent errors and ensure reliable behaviour . Caching is a technique where previously calculated or frequently accessed data is stored temporarily so it can be retrieved more quickly . This improves performance but can use extra memory and risks becoming outdated if the cached data no longer matches the current state . Reusable program components , such as functions , procedures and modules , are important because they reduce duplication , make programs easier to maintain , and allow well-tested code to be used across multiple solutions . YouTube video uploading soon Thinking Procedurally Pseudocode , program code and flowcharts are ways of representing a sequence of steps in an algorithm , showing clearly the order in which instructions should be carried out . Sub-procedures (such as functions and procedures ) are used in programs to break complex tasks into smaller , reusable parts , making the code easier to understand , test , maintain and debug . A structure diagram is a visual representation that shows how a program is broken down into its main components and sub-components , helping programmers plan the overall design and understand how different parts of the program fit together . YouTube video uploading soon Thinking Logically Decisions are needed in computer programs so that the software can choose different actions based on the data it receives or the situation it is in , rather than always following the same sequence of instructions. These decisions are controlled by logical conditions - statements that evaluate to true or false - which determine which path the program will take; for example, if score > 100 might trigger a bonus feature only when the condition is true . Because decisions allow the program to branch , they directly affect the flow of execution , enabling different outcomes , repeated actions or alternative processes depending on the conditions met . YouTube video uploading soon Thinking Concurrently Concurrency means designing a program so that multiple tasks can be processed at the same time , rather than strictly one after another. Programmers need to identify which parts of a program can safely run concurrently - for example, independent calculations or background tasks - and which parts must wait for others to finish because they rely on shared data or sequential results . Concurrent processing can bring benefits such as faster performance , better use of multicore processors and improved responsiveness , but it also introduces drawbacks, including increased complexity and the need for careful coordination to avoid errors when tasks depend on one another . YouTube video uploading soon This page is under active development. Check here for the latest progress update. Q uesto's K ey T erms Computational Thinking: abstraction, thinking abstractly, thinking ahead, precondition, caching, reusable components, thinking procedurally, thinking logically, concurrency, thinking concurrently D id Y ou K now? Building a Lego set is a great example of both abstraction and decompostition . For example, the Eiffel Tower Lego set is an abstracted version of it is real-life counterpart condensed into 10,001 pieces . There are over 75 numbered bags inside the box to follow instructions step-by-step to construct the 4'11" model . A-Level Topics 2.1 - Programming Techniques

Learn about on-site storage and cloud storage methods such as private, public, hybrid and community. 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 1.3 - Storage Watch on YouTube : On-Site Storage Cloud Storage Locations Cloud Storage Types There are five types of on-site (local ) storage you need to know - file servers , network attached storage (NAS ) devices, portable storage devices, solid state drives (SSD ) and storage area networks (SAN ). In regards to cloud storage , you need to know the different locations (private , public , hybrid and community ) and types (file , object , block , elastic /scalable and cloud-based database services . You need to be aware of the characteristics , advantages and disadvantages of each storage location and type as well as the factors to consider when selecting a storage location and type . What You Need to Know On-Site Storage On-site storage is physically located at the same site as the user or organisation , such as in a building or office , rather than being stored over the internet in the cloud . It gives the organisation direct control over its storage devices and data . File Servers File servers are central computers that store files for users on a network , allowing multiple people to access and share data from one location . They make it easy to manage files , set user permissions and perform backups in one place . However, they can be expensive to set up and maintain , and if the server fails , all users may lose access . Performance can also slow down if too many users access it at once . NAS Devices A network attached storage ( NAS ) device is a dedicated storage unit connected to a network , designed specifically for storing and sharing files . It is usually simpler and cheaper than a full file server , making it suitable for small networks or home use as they are easy to install and useful for backups . But they are less powerful , have limited scalability and their performance depends heavily on the network speed . Portable Storage Devices Solid States Drives (SSDs) Portable storage devices , such as USB flash drives and external hard drives , are small , removable devices that connect directly to a computer . They are highly portable , affordable and convenient because they do not require a network connection . However, they are easy to lose or damage , can pose security risks if stolen or infected with malware , and typically have less storage capacity than larger systems . SSDs are storage devices that use flash memory instead of moving parts and are commonly found inside computers or used externally . They offer very fast read and write speeds , are durable , silent and energy efficient . On the downside, they are more expensive than traditional hard drives , often have lower storage capacity for the price , and can wear out over time due to a limited number of write cycles . Storage Area Networks A storage area network ( SAN ) is a high-speed network that provides access to consolidated storage , typically used by large organisations . It allows for extremely fast data access , high reliability and can be scaled to store very large amounts of data . However, SANs are very expensive to implement , complex to manage and require specialist knowledge to maintain . Cloud Storage Locations Cloud storage is a way of storing data on servers that are accessed over the internet , allowing users to access their files from anywhere with an internet connection . Private Cloud Public Cloud A private cloud is used by a single organisation , either hosted on-site or by a third party . It offers high levels of control , security and customisation , making it suitable for organisations handling sensitive data or needing to comply with data privacy regulations . However, it is expensive to set up and maintain and the organisation is responsible for managing and updating the system. A public cloud is provided by external companies and shared between multiple users or organisations over the internet . Examples include Google Drive and Dropbox . It is cost-effective , easy to access from anywhere and requires no maintenance by the user . It is also scalable if more space is required at a later time and convenient . However, it offers less control over data , may raise security and privacy concerns and depends on a reliable internet connection . Hybrid Cloud A hybrid cloud combines both private and public cloud storage , allowing data to be shared between them . Organisations can keep sensitive data in the private cloud while using the public cloud for less critical data . This provides flexibility , cost efficiency and better security control . However, it can be complex to set up and manage and integrating the two systems can be challenging . Community Cloud A community cloud is shared by several organisations with similar needs , such as schools or government departments . The advantages include cost sharing , tailored security and easier collaboration between organisations . However, it may be less flexible than other cloud types and there can be concerns about data privacy and management between different organisations . Cloud Storage Types Cloud storage types are the different ways data can be organised , stored and accessed in the cloud , with each type designed for different uses and performance needs . File Storage File storage organises data in a hierarchical structure of folders and files, similar to how files are stored on a personal computer . It is easy to understand and use , making it ideal for shared drives and everyday file access due to its compatibility with many systems. However, it can become slow or inefficient with very large amounts of data and scaling up can be more difficult compared to other cloud storage types. Object Storage Object storage stores data as individual objects , each with metadata and a unique identifier , rather than in folders. It is designed for large amounts of unstructured data such as images , videos and backups . Its advantages include excellent scalability , high durability and cost-effectiveness for large datasets . However, it is not suitable for applications that require fast, frequent updates and it can be harder to work with compared to traditional file systems. Block Storage Elastic / Scalable Storage Block storage splits data into fixed-size blocks and stores them separately . It provides very fast access and high performance , making it suitable for systems that need quick read/write operations . The advantages are speed , reliability and flexibility . However, it is more complex to manage , can be expensive , and does not include built-in file organisation like file storage. Elastic storage automatically increases or decreases capacity based on demand . It is commonly used in cloud environments where storage needs change frequently . The main benefits are flexibility , cost efficiency ( only pay for what you use ) and no need to predict storage requirements in advance . However, costs can become unpredictable and it relies heavily on a stable internet connection and provider availability . Cloud-Based Database Services These are cloud services designed specifically to store and manage structured data using databases . They handle tasks such as backups , updates and scaling automatically . The advantages include ease of use , automatic maintenance , scalability and high availability . However, they can be costly over time , offer less control than self-managed databases and may raise concerns about data security and vendor lock-in . Q uesto's Q uestions 1.3 - Storage: 1. Choose the most storage type and explain your answer. [ 4 each ] a. A school wants a central place where all teachers can save and share files . b. A photographer needs to carry thousands of photos between clients. c. A bank needs extremely fast storage for critical systems . d. A company wants storage that automatically grows as it stores more data . e. A video streaming company needs to store millions of videos . 2. For each scenario , recommend a storage location and explain why. [ 4 each ] a. A hospital storing confidential patient records . b. A small business with a limited budget . c. A university working with several partner colleges . d. A company that wants to keep sensitive data private but also use cheaper cloud storage . 3. Give two advantages and two disadvantages for each cloud storage type (file storage , object storage , block storage , elastic / scalable storage, cloud-based database services . [4 each ] Every photo , video or file you upload to the cloud is often copied to multiple servers in different locations (this is called redundancy ). So if one server fails , your data can still be recovered . D id Y ou K now? 1.2 - Devices Topic List 2.1 - Data Formats & Types