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 the devices used to host applications, including consoles, desktops, haptics, laptops, servers, smart devices, tablets / hybrid devices and wearables. 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 1.2 - Devices Watch on YouTube : Devices You need to know the characteristics of the eight types of devices shown below that application platforms run on . You must also understand the advantages and disadvantages of each device . What You Need to Know Devices Game consoles are designed specifically for playing video games , usually connected to a TV . Desktops are powerful and customisable personal computers designed for use at a desk . Haptic devices allow users to feel vibrations with touch . Game controllers and smartphones use haptics. Laptops are portable computers with a built-in screen and keyboard , suitable for work on the go . Servers are powerful computers on a network that process requests sent by other systems. Smart devices connect to a network allowing it to communicate with other devices and be controlled remotely . Tablets use a large touchscreen and are more portable than a laptop , ideal for browsing and media . A hybrid device is a laptop with a detachable screen . Wearable devices such as a smartwatch are worn on the body and often monitor the user's condition in real-time . Q uesto's Q uestions 1.2 - Devices: 1. Choose the most appropriate device and explain your answer. [3 each ] a. A graphic designer needs maximum performance and wants to upgrade components over time . b. A student needs a computer to take to lessons and complete homework . c. A hospital wants to provide files and applications to hundreds of staff members . d. A gamer wants the easiest and cheapest way to play the latest games . e. An engineer is designing a virtual reality training simulation . f. A fitness enthusiast wants to track their heart rate and daily exercise . g. A salesperson needs a lightweight device for presentations and note-taking . h. A family wants a device for watching movies and using apps around the house . 2. Compare the following pairs . For each comparison , explain one similarity , two differences and which you would recommend for a given purpose. [ 4 each ] a. Desktop vs Laptop b. Laptop vs Tablet/Hybrid c. Console vs Desktop d. Smart Device vs Wearable Check out the Shorts on the CSNewbs YouTube channel if you are interested in how video game consoles have evolved over time . There are separate videos for PlayStation , Xbox and Nintendo consoles. D id Y ou K now? 1.1 - Application Platforms Topic List 1.3 - Storage Locations

Learn about operational issues including disaster planning, change management and data security. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification. 5.2 - Operational Issues Exam Board: OCR Specification: 2016 - Unit 1 What are operational issues? Operational issues refer to potential problems that could disrupt the workflow and efficiency of an organisation . They relate to processes within an organisation and the way that the company operates on a daily basis . Security of Information Definition: Organisations must ensure that data is stored securely to minimise the chances of data loss , corruption or unauthorised manipulation . Having information stolen through a hacking attempt, for example, would negatively impact the company and its customers and possibly lead to consequences such as poor publicity , a loss of business and reputation , fines and bankruptcy . One principle of the Data Protection Act is that data must be stored securely . Organisations can use security methods such as firewalls , antiviruses or physical protection such as biometrics to keep personal information secure . Health & Safety Definition: Ensuring that employees, clients and visitors are physically protected on-site . The organisation should create a health and safety policy that staff need to read and possibly sign at the start of their work placement. The policy should include information about how to avoid injury when using the systems, how to safely maintain the equipment and whom to contact for help . Disaster & Recovery Planning Important data is often stored on a computer network, so a detailed and effective disaster recovery policy must be in place in case an unexpected disaster occurs. Disasters include natural disasters (e.g. fire, flood, lightning), hardware failure (e.g. power supply unit failing), software failure (e.g. virus damage) and malicious damage (e.g. hacking). There are three clear parts to a disaster recovery policy: Before the disaster: All of the possible risks should be analysed to spot if there are any weaknesses in preparation. Preventative measures should be taken after the analysis, such as making rooms flood-proof or storing important data at a different location . Staff training should take place to inform employees what should happen in the event of a disaster. During the disaster: The staff response is very important – employees should follow their training and ensure that data is protected and appropriate measures are put in place. Contingency plans should be implemented while the disaster is taking place, such as uploading recent data to cloud storage or securing backups in a safe room and using alternative equipment until the disaster is over. After the disaster: Recovery measures should be followed, such as using backups to repopulate computer systems. Replacement hardware needs to be purchased for equipment that is corrupted or destroyed. Software needs to be reinstalled on the new hardware. Disaster recovery policies should also be updated and improved . Organisational Policies Definition: Creating policies that outline acceptable computer and network use . Workplaces and schools often require people to sign an acceptable use policy ( AUP ) before being allowed to use the network . An AUP may include the philosophy of the organisation , rules for the personal use of IT resources and the consequences of breaching the policy . An AUP is similar to codes of practice from 5.1 . Change Management Definition: Change management is a formal approach by an organisation to lead a change in the way a business or project is run . This may include editing budgets , redefining expected deadlines , reconsidering how resources are used or changing staff roles . Advantages of change management: Reduces the likelihood of things going wrong during development. Creates a clear log of changes and improvements that are to be made. Allows changes to be approved and discussed before they happen. Formalises the process and sets out clear rules for changes . Disadvantages of change management: Can make the process of change more complicated . It can reduce the responsiveness of developers if everything must go through a formal process. It can be challenging to implement successfully. To work effectively, it needs everyone to follow the process . Scales of Change There are two main reasons why major change will occur in an organisation. Change Drivers Definition: Companies must change to stay up to date with the times and new technology . Change drivers are factors that force a business to change , such as: New legislation New competitors in the market New platforms (e.g. mobile technology and game consoles) to sell products on Economic changes Changes in business practice Social changes Change Needs Definition: Companies must change if the needs and focus of the organisation are altered over time . This reflects the changing needs of the business , often due to advancements in technology , such as: New equipment (e.g. replacing a slow network with a faster fibre optics network) Customer interaction (e.g.communicating with customers in new ways, such as social media apps) Workplace shifts (e.g. providing remote access for employees to access work and services at home) Q uesto's Q uestions 5.2 - Operational Issues: 1. Describe 3 possible consequences to an organisation if data is not stored securely . [6 ] 2. Describe the purpose of a health and safety policy and state 3 things that may be included in one. [4 ] 3a. Describe, giving specific examples , different types of possible disaster . [5 ] 3b. Describe the steps an organisation should take before , during and after a disaster occurs . [10 ] 4. Describe 3 things that may be included within an Acceptable Use Policy (AUP ). [3 ] 5a. What is change management ? Give 2 examples of when change management may be used. [4 ] 5b. Describe the advantages and disadvantages of a company deciding to implement change management . [8 ] 6a. Describe the difference between change drivers and change needs . [2 ] 6b. Describe 3 examples of change drivers and 3 examples of change needs . [6 ] 5.1 - Ethical Issues Topic List 5.3 - Threats

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

Learn how to change the colour of text in Python using the colorama library. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 5d - COlorama What is Colorama? Colorama is a library that allows the colour of text to be changed. Information about the library can be found on the Python Package Index (PyPi) website . Copyright of the library is held by Jonathan Hartley & Arnon Yaari. Colorama can be imported when using some online editors like Replit . Colorama is not available as a default library on the standard Python offline editor (IDLE) . Using Colorama The three main commands using Colorama are: Fore to change the text colour. Back to change the highlight colour. Style to make the text appear dim or bright. from colorama import Fore print (Fore. GREEN + "Hello There" ) Hello There from colorama import Back print (Back.YELLOW + "Goodbye Now" ) Goodbye Now from colorama import Style print (Style.DIM + "Hi Again" ) Hi Again There are 8 possible colours to choose with the Fore and Back commands. You must write the colour name in CAPITAL LETTERS . BLACK CYAN GREEN MAGENTA RED WHITE YELLOW There is also the RESET option, e.g. Fore.RESET The 2 options to choose with the Style command are DIM and BRIGHT . You can also use Style.RESET_ALL Colorama Task 1 ( Traffic Lights) Create a simple traffic light program . The user is prompted for an input . Typing "GO " will output a suitable message in GREEN , typing "WAIT " will output a message in YELLOW and typing "STOP " will output a response in RED . Example solutions: What should the driver do? STOP You must stop your car. What should the driver do? GO It is safe to continue driving. ⬅ 5c - Date & Tim e 5e - M ore Libraries ➡

Consider multiple extensions to increase the complexity of your Greenfoot game. Part 7 of the Greenfoot Tutorial for the Eduqas / WJEC GCSE 2016 specification. 7. Extension Ideas Greenfoot Tutorial This concludes the tutorial for a simple Greenfoot game! Try a combination of the suggestions below to add complexity to your game: 1. Make a New Class for 'Bad' Collectibles Create a new subclass in the Actor classes section for a new collectible that will lower the score if picked up. Add code to your main character to remove the collectible when they touch . Add code to decrease the counter by 1 at the same time. 2. Make the Collectibles Move Randomly Copy the code from your enemy class that makes it move randomly and bounce on edge , and paste this into your collectible class . This makes it harder to catch the collectables, especially if there are 'bad' objects to avoid. 3. Stop the Game Go to the code of your enemy and add the line underlined in red within your removal code. This will stop the game if your main character is eaten. 4. Make the Game Multiplayer Create a new subclass in the Actor classes section for a new main character that will be controlled by a second player . Add code to your new character to move it right, down, left and up . Choose different keys for each direction , such as the WASD keys or IJKL keys. If the second player touches a collectible , add code to decrease the score . Multiplayer Rules: Player 1 wins if the final score is above 0 . Player 2 wins if the final score is negative . It is a draw if it finishes on 0 . < Part 6 - The Counter

Learn about security threats, including botnets and DDoS attacks and both physical and digital security mitigations. 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 4.1 - Security Considerations Watch on YouTube: Security threats Physical security Digital security You need to know the risks that specific security threats pose to applications , including botnets , DDoS attacks , hacking and malware . You need to know how both physical security mitigations (e.g. biometrics , locks and RFID ) and digital security mitigations (e.g. encryption , firewalls and anti-malware ) protect application software against threats . What You Need to Know Security Threats Common threats to application software include: Botnet A botnet is a group of compromised devices that are remotely controlled by an attacker , often without their owners knowing , and used together to carry out malicious activities . DoS / DDoS Attack A Denial of Service (DoS ) attack attempts to make a system or service unavailable by overwhelming it with requests or traffic . A Distributed Denial of Service (DDoS ) attack does this using many devices at the same time , often through a botnet . Hacking Hacking is the process of gaining unauthorised access to a computer system , network or data . This potentially allows data to be viewed , changed , stolen or deleted . Lack of Supplier Support A lack of supplier support occurs when a developer no longer provides updates , security patches or technical assistance for its software , leaving newly discovered vulnerabilities potentially unfixed . Malicious Spam Malicious spam is unwanted messages sent to large numbers of users that contain harmful or deceptive content . This may include links designed to steal information or distribute malware . Malware Malware is software intentionally designed to damage , disrupt or gain unauthorised access to systems or data . Examples include viruses , worms , ransomware and spyware . Out-of-date Software Out-of-date Hardware Out-of-date Firmware Out-of-date software may contain known security vulnerabilities that newer versions have fixed , making it easier for attackers to compromise the system . Out-of-date hardware may lack modern security features , be incompatible with newer security software or no longer receive support from its manufacturer . Firmware is software built into a device that controls how its hardware operates . Out-of-date firmware may contain unpatched security vulnerabilities that attackers could exploit to access or interfere with the device . Physical Security Mitigations Physical security mitigations are measures used to prevent unauthorised physical access to systems that run application software . Biometrics Biometrics use unique physical characteristics, such as fingerprints or facial features , to verify a person's identity and prevent unauthorised users from physically accessing devices and application software . Cable Locks Cable locks physically secure devices such as laptops to a fixed object like a table , reducing the risk of equipment being stolen and the application software or data on it being accessed . Cameras Cameras like CCTV can monitor and record areas containing computer equipment , helping to deter unauthorised access or theft and providing evidence if a security incident occurs . Locks Locks restrict physical access to rooms , cabinets or equipment for unauthorised people , helping prevent devices and the application software they contain from being accessed , stolen or damaged . RFID Radio Frequency Identification (RFID ) uses radio waves to communicate wirelessly between an RFID tag or card and a reader . It can be used to identify authorised users and control physical access to restricted areas , such as server rooms . Safe A safe provides secure physical storage for devices or storage media , protecting them against unauthorised access , theft and potentially physical damage . Swipe Cards Swipe cards require users to swipe or scan an authorised card to enter restricted areas , preventing unauthorised people from physically accessing devices and systems containing application software . Digital Security Mitigations Digital security mitigations use software and technology to protect applications and data from security threats . Access Rights Access rights control what resources and actions different users are allowed to access , such as viewing , editing or deleting data . This helps prevent unauthorised access or changes . Anti-Malware Anti-malware is software that detects , blocks and removes malware , such as a virus or worm . It helps prevent malicious software from damaging applications , stealing data or gaining unauthorised access . Back-up A back-up creates a separate copy of data that can be restored if the original is lost , damaged or corrupted , for example following a malware attack or hardware failure . Cryptography Cryptography uses mathematical techniques to protect data and communications , helping keep data confidential , verify its authenticity and prevent unauthorised changes . 2FA Two-factor authentication (2FA ) requires a user to provide two different forms of authentication before gaining access , such as a password plus a code from another device . This makes unauthorised access more difficult if one factor is compromised . Encryption Encryption converts data (plaintext ) into an unreadable form (ciphertext ) that requires the correct key to decrypt . It prevents unauthorised users from understanding the data if they gain access . Encryption at rest protects stored data , such as files on a device or records in a database , if the storage is accessed or stolen . Encryption in transit protects data while it is being transferred across a network , reducing the risk of intercepted data being read . Firewall A firewall monitors and controls network traffic using security rules , helping prevent unauthorised or suspicious connections . A hardware firewall is a physical network device , often built into a router , that can protect multiple devices by filtering traffic entering or leaving a network . A software firewall is installed on a specific device that monitors and controls network traffic for that device and its applications . Q uesto's Q uestions 4.1 - Security Considerations: 1. Describe the following security threats : botnets , DoS/DDoS attacks , hacking , lack of supplier support , malicious spam and malware . [ 2 each ] 2. Explain why out-of-date software , hardware and firmware can create security risks for application software . [3 ] 3. Explain how physical security measures , including biometrics , cable locks , cameras , locks , RFID , safes and swipe cards , can protect application software and systems. [2 each ] 4. Explain how access rights , anti-malware , backups , cryptography , encryption , firewalls and 2FA can protect application software from security threats. [2 each ] 5. For an online mobile game , recommend suitable physical and digital security mitigations and justify how they would protect against specific threats . [6 ] The WannaCry ransomware attack of 2017 affected hundreds of thousands of computers worldwide , including NHS systems . It exploited a vulnerability in older or unpatched Windows systems and resulted in an estimated 19,000 NHS appointments and operations being cancelled . D id Y ou K now? 3.2 - Protocols Topic List 5.1 - Testing

Learn about the four types of secondary storage - magnetic, optical, solid-state and cloud. Also, learn about the data storage units from bit to yottabyte. Based on the 2020 Eduqas (WJEC) GCSE specification. 1.4: Secondary Storage & Data Units Exam Board: Eduqas Specification: 2020 Secondary storage (also known as backing storage ) is non-volatile storage used to save and store data that can be accessed repeatedly. Secondary storage is not directly embedded on the motherboard (and possibly even external ) and therefore further away from the CPU so it is slower to access then primary storage . Storage Characteristics: CAPACITY : The maximum amount of data that can be stored. DURABILITY : The physical strength of the device, to withstand damage. PORTABILITY : How easy it is to carry the device around. ACCESS SPEED : How quickly data on the device can be read or edited . COST : The average price it costs to purchase a storage device. Magnetic Storage Optical Storage A magnetic hard disk drive (HDD ) is the most common form of secondary storage within desktop computers. A read/write head moves nanometres above the disk platter and uses the magnetic field of the platter to read or edit data. An obsolete (no longer used) type of magnetic storage is a floppy disk but these have been replaced by solid state devices such as USB sticks which are much faster and have a much higher capacity. Another type of magnetic storage that is still used is magnetic tape . Magnetic tape has a high storage capacity but data has to be accessed in order (serial access ) so it is generally only used by companies to back up or archive large amounts of data . Optical storage uses a laser to project beams of light onto a spinning disc, allowing it to read data from a CD , DVD or Blu-Ray . This makes optical storage the slowest of the four types of secondary storage. Disc drives are traditionally internal but external disc drives can be bought for devices like laptops. Magnetic Storage Characteristics: ✓ - Large CAPACITY and cheaper COST per gigabyte than solid state . X - Not DURABLE and not very PORTABLE when powered on because moving it can damage the device. X - Slow ACCESS SPEED but faster than optical storage . Optical Storage Characteristics: X - Low CAPACITY : 700 MB (CD ), 4.7 GB (DVD ), 25 GB (Blu-ray ). X - Not DURABLE because discs are very fragile and can break or scratch easily. ✓ - Discs are thin and very PORTABLE . Also very cheap to buy in bulk. X - Optical discs have the Slowest ACCESS SPEED . Magnetic Disks are spelled with a k and Optical Discs have a c. Solid State Storage Cloud Storage There are no moving parts in solid state storage. SSD s (Solid State Drives ) are replacing magnetic HDDs (Hard DIsk Drives) in modern computers and video game consoles because they are generally quieter , faster and use less power . A USB flash drive ( USB stick ) is another type of solid state storage that is used to transport files easily because of its small size. Memory cards , like the SD card in a digital camera or a Micro SD card in a smartphone , are another example of solid state storage. When you store data in 'the cloud', using services such as Google Drive or Dropbox, your data is stored on large servers owned by the hosting company . The hosting company (such as Google) is responsible for keeping the servers running and making your data accessible on the internet . Cloud storage is very convenient as it allows people to work on a file at the same time and it can be accessed from different devices. However, if the internet connection fails , or the servers are attacked then the data could become inaccessible . Solid State Characteristics: X - High CAPACITY but more expensive COST per gigabyte than magnetic . ✓ - Usually DURABLE but cheap USB sticks can snap or break . ✓ - The small size of USB sticks and memory cards mean they are very PORTABLE and can fit easily in a bag or pocket. ✓ - Solid State storage has the fastest ACCESS SPEED because they contain no moving parts . Cloud Storage Characteristics: ✓ - Huge CAPACITY and you can upgrade your subscription if you need more storage. ✓ / X - Cloud storage is difficult to rank in terms of PORTABILITY , DURABILITY and ACCESS SPEED because it depends on your internet connection. A fast connection would mean that cloud storage is very portable (can be accessed on a smartphone or tablet) but a poor connection would make access difficult . ✓ - Cloud storage is typically free for a certain amount of storage. Users can then buy a subscription to cover their needs - Dropbox allows 2 GB for free or 2 TB for £9.99 a month. Data Storage Units 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 . 1,024 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 . 1,024 kilobytes is called a megabyte . A megabyte can store about a minute of music . 1,024 megabytes is called a gigabyte . A gigabyte can store about 500 photos . 1,024 terabytes is called a petabyte . A petabyte can store about 1.5 million CDs . 1,024 gigabytes is called a terabyte . A terabyte can store about 500 hours of films . More data storage units: 1,024 petabytes is called a exabyte . 1,024 exabytes is called a zettabyte . 1,024 zettabytes is called a yottabyte . Q uesto's Q uestions 1.4 - Secondary Storage: 1. Rank magnetic , optical and solid-state storage in terms of capacity , durability , portability , speed and cost . For example, magnetic has the highest capacity , then solid-state, then optical. This could be completed in a table . [15 ] 2. Justify which secondary storage should be used in each scenario and why it is the most appropriate: a. Sending videos and pictures to family in Australia through the post . [ 2 ] b. Storing a presentation to take into school . [ 2 ] c. Storing project files with other members of a group to work on together . [ 2 ] d. Backing up an old computer with thousands of files to a storage device. [ 2 ] 3. Put the following data storage units in order from smallest to largest : a . kilobyte - gigabyte - byte - megabyte - nibble - bit [3 ] b. gigabyte - petabyte - kilobyte - exabyte - terabyte - megabyte [ 3 ] 1.3 - Primary Storage 1.5 - Performance Theory Topics

Learn how to use the math library and to refresh the screen (on some editors only). Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 5e - More Libraries Clear Screen Importing the os library and using the .system() command with the "clear" parameter will clear the screen . The console won't clear on offline editors like IDLE but will work with many online editors like Replit. import os print ( "Hello" ) os. system ( "clear" ) print ( "Bye" ) Bye Clear Screen Task ( Trivia Questions ) Ask three trivia questions of your choice to the user and clear the screen between each one. You should display the total they got correct after the third question - to do this you need to set a variable called correct to equal 0 at the start and then add 1 to correct each time a correct answer is given . Example solution: The Math Library The math libraries contains several commands used for numbers: sqrt to find the square root of a number. ceil to round a decimal up to the nearest whole number and floor to round down to the nearest whole number. pi to generate the value of pi (π ). The sqrt command will find the square root of a number or variable placed in the brackets and return it as a decimal number . from math import sqrt answer = sqrt(64) print (answer) 8.0 The ceil command rounds a decimal up to the nearest integer and the floor command rounds a decimal down to the nearest integer . from math import ceil, floor answer = 65 / 8 print ( "True answer:" , answer) print ( "Rounded up:" , ceil(answer)) print ( "Rounded down:" , floor(answer)) True answer: 8.125 Rounded up: 9 Rounded down: 8 The pi command generates a pi value accurate to 15 decimal places . Pi is used for many mathematical calculations involving circles . The area of a circle is pi x radius² . The first example below uses 5.6 as the radius . from math import pi radius = 5.6 area = pi * (radius * radius) print ( "The area of the circle is" , area) The area of the circle is 98.5203456165759 The example below uses an input to allow the user to enter a decimal (float ) number for the radius. It also uses the ceil command to round the area up . from math import pi, ceil radius = float(input( " Enter the radius: " )) area = pi * (radius * radius) print ( "The area of the circle is" , ceil(area)) Enter the radius: 2.3 The area is 17 Clear Screen Task ( Area of a Sph ere ) The formula of a sphere is 4 x π x r² where π represents pi and r is the radius . Use an input line to enter the radius and then calculate the area of the sphere . Round the answer down to the nearest integer using floor and print it. Example solution: Enter the radius: 7.1 The area of the sphere is 633 ⬅ 5d - Coloram a Section 5 Practice Tasks ➡

Learn about different forms of malware including virus, worm and trojan. Learn about the different ways that malware can infect a computer system. Malware Malware is any type of harmful program that seeks to damage or gain unauthorised access to your computer system. Part 1: SiX Types of Malware Virus A virus can replicate itself and spread from system to system by attaching itself to infected files . A virus is only activated when opened by a human . Once activated, a virus can change data or corrupt a system so that it stops working . Trojan A trojan is a harmful program that looks like legitimate software so users are tricked into installing it . A trojan secretly gives the attacker backdoor access to the system . Trojans do not self replicate or infect other files. Ransomware Ransomware locks files on a computer system using encryption so that a user can no longer access them. The attacker demands money from the victim to decrypt (unlock) the data . ? ? Attackers usually use digital currencies like bitcoin which makes it hard to trace them. Spyware Spyware secretly records the activities of a user on a computer. The main aim of spyware is to record usernames, passwords and credit card information . All recorded information is secretly passed back to the attacker to use. Keylogger A keylogger secretly records the key presses of a user on a computer. Data is stored or sent back to the attacker. The main aim of a keylogger is to record usernames, passwords and credit card information . Keyloggers can be downloaded or plugged into the USB port . Worm A worm can replicate itself and spread from system to system by finding weaknesses in software . A worm does not need an infected file or human interaction to spread. A worm can spread very quickly across a network once it has infiltrated it. Part 2: Four ways malware cAN infect your system 1. A ccidentally downloading an infected file from an insecure website . 2. Phishing emails - clicking on attachments or links in spam emails . 3. Installing malware from a physical device, e.g. USB stick . 4. Self-replicating malware , such as worms , spreading across a network . Phishing & Staying Safe

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

Learn about the benefits of compression and the differences between lossy and lossless compression. Also, learn how compression ratios work. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 2.5: Compression Exam Board: OCR Specification: J277 Watch on YouTube : Compression Benefits Lossy Compression Lossless Compression What is compression? To compress a file means to make its size smaller . Benefits of compression include: Files take up less storage space (so more files can be stored). Files can be transferred quicker (because they are smaller). Files can be read from or written to quicker . There are two methods that are used to compress files: Lossy and Lossless . Lossy Compression Lossy compression uses an algorithm (set of instructions) to analyse a file and remove data that cannot be heard or seen by humans . For example, a lossy algorithm would analyse the sound waves of an audio file and remove any frequencies which humans cannot hear. This process reduces the size of the file . Further lossy compression will remove data that humans can see / hear . For example, the dog image to the right has been strongly compressed using a lossy algorithm and some data has clearly been removed. Lossy compression removes the data permanently , so the file can never return to its original form . Lossy compression is often used with images , audio and video to reduce the file size, for example to send over the internet. Lossless Compression Lossless compression reduces the size of a file without permanently removing any data . Because of this, the file is returned to its original form when decompressed, so no quality is lost . A file that is compressed with a lossless algorithm is usually larger than a file compressed with a lossy algorithm because no data has been permanently removed. Lossless compression is used with files that would not function properly if data were permanently removed, such as executable files (e.g., programs and games) or word documents . Remember that lossy and lossless compression do not just refer to images. Below is an audio file that has been compressed with lossy compression . Data has been removed so the audio quality has decreased. 197 KB 81 KB 43 KB Q uesto's Q uestions 2.5 - Compression: 1. Describe 3 benefits of compressing a file . [ 3 ] 2. Describe the differences between lossy and lossless compression . [4 ] 3. A student needs to compress a Microsoft Word document to send in an email. Suggest which type of compression they should use and why . [ 2 ] 2.4e Sound Storage Theory Topics 3.1a - Network Types & Performance