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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 the differences and characteristics of programs and applications. Resources based on Unit F160 (Fundamentals of Application Development) for the OCR Cambridge Advanced Nationals in Computing (H029 / H129) AAQ (Alternative Academic Qualification). Qualification: Cambridge Advanced National in Computing (AAQ) Unit: F160: Fundamentals of Application Development Certificate: Computing: Application Development (H029 / H129) 1.1 - Programs & Applications Watch on YouTube : Programs & Applications The terms 'program ' and 'application ' do not mean the same thing. A program performs individual operations while an application may use several programs together to create a functional tool for a user . For example, a program may calculate the total of a range of numbers . An example of an application is Microsoft Excel , which is spreadsheet software with a range of programs built in , including the ability to calculate totals , as well as many other functions . Programs and Applications Every topic in Unit F160 ( Fundamentals of Application Development ) comes with YouTube videos to help you learn . Some pages only have one video , while others have several . Programs Applications A program is a set of instructions that a computer can understand and execute to perform specific tasks . It is written in a programming language like Python or Java and instructs the computer how to perform individual operations . Programs can be simple (e.g. printing a message to the screen) or complex (e.g. managing a database or running a web server ). An application is a type of program designed to be user-friendly and help users complete specific tasks . Examples of applications include word processors (e.g. Microsoft Word), web browsers (e.g. Google Chrome) and mobile apps (e.g. Instagram). Applications are made up of one or more programs . Examples A program has a specific purpose , that is understood and executed by the computer . An example is a program that can sort data into alphabetical order . This may be used in an application like spreadsheet software . A video editing application may include several programs , each with a specific purpose , such as a program to import video , one to apply filters , another to edit audio and another to export the finished video . Characteristics Characteristics of a program: Programs are created using programming languages like Python or Java . They are translated into a format the computer understands and then run . Each program is designed to perform a specific function or set of functions . They may not have a user interface and may not require user interaction , such as an operating system's background processes . Programs may consist of smaller sub-programs that can be reused in different applications . Characteristics of an application: Applications are designed to meet user requirements . They are designed for specific tasks , such as editing photos or sending emails. Most have a user interface to provide a way for humans to interact with the application, e.g. menus and buttons . Applications may be designed to run on specific operating systems , such as an iPhone app designed for iOS. They may involve multiple programs working together . Devices that use Programs and Applications Every type of computer system will use programs and/or applications for different, specific purposes . Desktops and laptops run operating systems , software applications and utilities . Game consoles use applications for gaming , streaming and social features like group voice chats. Smart TVs use apps for streaming and browsing and programs for remote control . Smart speakers use programs to process voice commands , control smart home devices and play music based on user input . Smartphones and tablets use mobile apps for communication , games and productivity . AR (augmented reality ), VR (virtual reality ) and MR (mixed reality ) devices use programs to generate and manage 3D environments , track user movements and respond to inputs . Embedded systems like washing machines , smart fridges and cars use programs to manage their operations and interfaces . Q uesto's Q uestions 1.1 - Programs & Applications: 1. Explain the differences between a program and an application , using examples . [4 ] 2. Give 3 characteristics of a program and 3 features of an application . [6 ] 3. Briefly summarise how four different devices would use programs or applications . [4 ] As of 2025 , the Google Play Store has over 3.5 million apps and is close to reaching 150 billion downloads ! D id Y ou K now? Topic List 1.2 - Operating Systems

Learn about the three factors that affect computer performance - cache memory size and levels, clock speed and the number of cores. Based on the 2020 Eduqas (WJEC) GCSE specification. 1.5: Performance Exam Board: Eduqas / WJEC Specification: 2020 + The performance of a computer system is affected by three main factors: Cache Memory: Size & Levels What is cache memory? Cache memory is temporary storage for frequently accessed data . Cache memory is very quick to access because it is closer to the CPU than other types of memory like RAM . What are the 3 levels of cache memory? Level 1 cache is the smallest level but it is also the fastest . Level 2 cache is larger than level 1 but slightly slower. Level 3 cache is located outside of the CPU core which makes it slower than the first two levels but it is much larger . How does cache memory work? When the CPU searches for data , it looks first in level 1 cache, then level 2 and then level 3 . If the data has been found , this is called a 'cache hit '. If the data is not found then the CPU searches in RAM instead which takes more time - this is called a 'cache miss '. How does cache memory improve performance? Cache memory is closer to the CPU than RAM , meaning that it can provide data and instructions to the CPU at a faster rate . A computer with more cache memory (e.g. 8MB instead of 4MB) should have a higher performance because repeatedly used instructions can be stored and accessed faster . Larger level 1 and level 2 cache sizes will improve a computer's performance as data can be accessed extremely quickly . What is the limitation of cache memory? Cache memory is costly, so most computers only have a small amount . Multiple cache misses will result in data latency (delay) as information is accessed from RAM which is further away from the CPU. Clock Speed What is clock speed? Clock speed is the measure of how quickly a CPU can process instructions . Clock speed is measured in Gigahertz (GHz) . A typical desktop computer might have a clock speed of 3.5 GHz . This means it can perform 3.5 billion cycles a second . How does clock speed improve performance? The faster the clock speed, the faster the computer can perform the FDE cycle resulting in better performance because more instructions can be processed each second . How does overclocking and underclocking affect performance? Typical clock speed: 3.5 GHz Underclocking Overclocking 3.9 GHz 3.1 GHz Overclocking is when the computer's clock speed is increased higher than the recommended rate. This will make the computer perform faster, but it can lead to overheating and could damage the machine . Underclocking is when the computer's clock speed is decreased lower than the recommended rate. This will make the computer perform slower but will increase the lifespan of the machine . Number of Cores What is a core? A core is a complete set of CPU components (control unit, ALU and registers). Each core is able to perform its own FDE cycle . A multi-core CPU has more than one set of components within the same CPU. How does the number of cores improve performance? In theory, a single-core processor can execute one instruction at a time , a dual-core processor can execute two instructions, and a quad-core can execute four instructions simultaneously . Therefore, a computer with more cores will have a higher performance because it can process more instructions at once . What are the limitations of having more cores? If one core is waiting for another core to finish processing, performance may not increase at all. Some software is not written to make use of multiple cores , so it will not run any quicker on a multi-core computer. Q uesto's Q uestions 1.5 - Performance: Cache Size & Levels 1a. What is cache memory ? [ 2 ] 1b. Describe the three levels of cache memory . [ 3 ] 1c. Describe what is meant by a ' cache hit ' and a ' cache miss '. [ 2 ] 1d. Describe two ways that more c ache memory will mean performance is higher . [ 4 ] 1e. Explain why most computers only have a small amount of cache memory. [ 1 ] Clock Speed 2a. What is clock speed ? What is it measured in? [ 2 ] 2b. Explain how a higher clock speed improves performance . [ 2 ] 2c. Explain the terms 'overclocking ' and 'underclocking ' and explain the effects of both on the performance of a computer. [ 4 ] Number of Cores 3a. What is a core ? [ 2 ] 3b. Explain why a quad-core processor should have a higher performance than a dual-core processor . [ 3 ] 3c. Explain two reasons why having more cores doesn't necessarily mean the performance will be better . [ 2 ] 1.4 - Secondary Storage 1.6 - Additional Hardware Theory Topics

Test your understanding of subroutines (procedures and functions) in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python - Section 7 Practice Tasks Task One Example solution: Create a program with three different subroutines (procedures ). One subroutine asks the user their name and prints a response. The second asks for their age and prints a response. The third asks for their favourite colour and prints a response. Remember to write subroutines before the main program. Task Two Create a program that asks a user to input the length of a side in a square. Write a function that takes this value and returns it to be printed. Example solution: Task Three Example solution: Create a program that takes 3 inputs from the user – a name, a villain and a place. Write a function that outputs a story using the user’s answers. Task Four Create a calculator program that uses four different subroutines (add, subtract, multiply and divide). In the main program ask the user to make a choice of which operator to use and then to enter two numbers. Keep looping until the user types stop. Use the 'Using Subroutines as a Menu' section in the 7b to help you. Example solution: ⬅ 7b - Functions 8a - Using Lists ➡

Learn about six network devices - hub, switch, router, bridge, WAP and NIC. Also, learn about routing tables and cost diagrams. Based on the 2020 Eduqas (WJEC) GCSE specification. 3.4: Network Hardware & Routing Exam Board: Eduqas / WJEC Specification: 2020 + Network Devices Hub A hub receives data packets from a connected device and transfers a copy to all connected nodes . Switch A switch receives data packets , processes them and transfers them on to the device specifically listed in the destination address of the packet. Router Routers are used to transfer data packets between networks . Data is sent from network to network on the internet towards the destination address listed in the data packet. A router stores the address of each computer on the network and uses routing tables to calculate the quickest and shortest path . Bridge A bridge joins together two networks that use the same base protocols . For example, a bridge could link together a LAN to another LAN . Wireless Access Point (WAP) Provides a link between wireless and wired networks . It creates a wireless local area network that allows WiFi enabled devices to connect to a wired network. Network Interface Card (NIC) A Network Interface Card (often shortened to NIC ) is an internal piece of hardware that is required for the computer to connect to a network . It used to be a separate expansion card but now it is commonly built directly into the motherboard (and sometimes known as a network adapter ). Wireless network interface cards ( WNIC ) permit a wireless network connection. Routing A routing table is a list of the optimal routes for data packets to be sent from one device to another. Routing tables should be kept accurate and up to date to ensure that packets are transferred as quickly as possible . During routing the lowest cost route is calculated . This is the shortest path with the fastest nodes to transfer data. Below is a simplified network and basic routing table showing the lowest cost (optimal) route using node A as the source address. Q uesto's Q uestions 3.4 - Network Hardware & Routing: 1a. Describe the difference between a hub and a switch . [ 2 ] 1b. Explain how a modem works. [ 2 ] 1c. Describe the purpose of a router . [ 2 ] 1d. Describe the difference between a gateway and a bridge . [ 2 ] 1e. State what WAP stands for and describe its purpose . [ 2 ] 1f. State what NIC stands for and why it is required . [ 2 ] 2a. Describe what a routing table is and why they should be maintained . [ 2 ] 2b. In terms of routing, what does a low-cost route mean? [ 2 ] 2c. Copy and complete the routing table below using node J as the source address . [ 4 ] 3.3 - Network Topology Theory Topics 3.5 - Protocols

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

A key term generator to display randomised or sequential terms from the OCR A-Level Computer Science (H446) course. Filter terms by topics and 'favourite' tricky terms to focus on later. Perfect for students learning A-Level Computer Science in UK schools. A-Level Key Terms Generator If you see this message, your school may be using a strict network filter which has blocked it. The tool uses basic JavaScript and should work fine on a home network. Use this tool to check your understanding of the OCR A-Level Computer Science H446 specification's key terms . OCR A-Level Homepage

Learn about lossy and lossless compression and the lossless compression algorithms run-length encoding and dictionary coding. This topic also covers symmetric and asymmetric encryption and the uses of hashing. Based on the OCR H446 Computer Science A-Level specification. Exam Board: OCR A-Level 3.1 - Compression, Encryption and Hashing Specification: Computer Science H446 Watch on YouTube : Lossy & Lossless Compression Lossless Compression Algorithms Encryption Hashing Lossy vs Lossless Compression Compression is the process of reducing the size of a file so it takes up less storage space and can be transmitted more quickly over a network . It works by encoding data more efficiently or removing unnecessary information . Benefits of compression include faster file transfer speeds , reduced storage requirements and improved performance when streaming data . Lossy compression permanently removes some data that is less important to human perception , such as subtle sounds or image details , resulting in smaller file sizes but slightly lower quality . Lossless compression reduces file size without losing any data , allowing the original file to be perfectly restored after it is decompressed . Lossless Compression Algorithms There are two types of lossless compression that you need to know: Run-Length Encoding (RLE ) is a simple form of lossless compression that reduces file size by storing repeating data as a single value and a count . For example, a sequence like AAAAABBBCCCC could be stored as A5B3C4 , saving space in files with many repeated elements , such as pixels in images . Dictionary Encoding replaces repeating patterns of data with shorter codes that reference entries in a dictionary . The dictionary stores common sequences once , and each repetition is replaced by a shorter reference , making it efficient for text and other data with recurring patterns . YouTube video uploading soon Encryption Encryption is the process of converting readable data (plaintext ) into an unreadable form (ciphertext ) to prevent unauthorised access . It ensures the confidentiality and security of information during storage or transmission . There are two key types of encryption : Symmetric encryption uses the same key for both encryption and decryption , meaning the sender and receiver must share the key securely . It is fast and efficient , making it suitable for encrypting large amounts of data . However, key distribution is a major risk if the key is intercepted . Asymmetric encryption uses a pair of keys - a public key for encryption and a private key for decryption . It is more secure for communication but slower due to complex mathematical processes . Asymmetric encryption is often used to exchange symmetric keys securely before data transfer . YouTube video uploading soon Hashing Hashing is the process of applying a mathematical function (hash function ) to data to produce a fixed-size value , known as a hash . It is a one-way process , meaning the original data cannot be reconstructed from the hash . Hashing is commonly used for data integrity checks , password storage and digital signatures . Even a tiny change in the input data produces a completely different hash , making it useful for detecting tampering or corruption . YouTube video uploading soon This page is under active development. Check here for the latest progress update. Q uesto's K ey T erms Compression: lossy compression, lossless compression, run-length encoding, dictionary encoding Encryption: plaintext, ciphertext, key, symmetric encryption, asymmetric encryption Hashing: hash function, hash D id Y ou K now? Alan Turing and his team used pattern recognition to analyse recurring sequences in encrypted German messages , helping to break the Enigma code , which was a major factor in the Allies’ victory in World War II . 2.4 - Programming Languages A-Level Topics 3.2 - Databases

Learn about the characteristics of information and the impacts of both good and poor quality information on customers and stakeholders. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification for Unit 2 (Global Information). 2.3 - Quality of Information Exam Board: OCR Specification: 2016 - Unit 2 Information Characteristics Valid Information This is correct, up-to-date and complete information that fits its purpose . For example, detailed end-of-year financial data in the form of graphs. Biased Information This is technically correct, but slanted , information that presents a one-sided view . For example, end-of year financial data that focuses on profits and ignores significant losses. Relevant Information Information should be appropriate for the required purpose . Irrelevant information may get in the way of correct decision making. Accurate Information Information should be carefully selected and entirely correct , inaccurate information can lead to unwanted consequences such as higher costs and missed deadlines. Reliable Information Information from a source that can be verified and confirmed to be correct . For example, BBC News is a more reliable information source than social media posts. Information Quality The quality of information that an organisation uses will have a significant impact on further processes and decisions. Good quality information that is accurate , valid or reliable can lead to better strategic decisions , meeting deadlines and innovation . Poor quality information that is biased , inaccurate or out of date may lead to negative consequences such as loss of customer trust , fines and legal challenges . Positive Effects of Good Quality Information Reliable information received by the management team . Good quality research information. Good quality sales information. Accurate cost projection information. Informed decisions with a higher chance of success . Can lead to innovation and better understanding . Strategic decisions and planning ahead . Projects will stay within their budget . Accurate time expectations . Projects will be completed on time . Negative Effects of Poor Quality Information Biased survey with inaccurate results . Inaccurate stock information. Out of date information received by management . Inaccurate data has led to poor reviews online . Inaccurate time expectations . Misinformed decisions , not responding to customers needs . ??? Inaccurate delivery times , customers unhappy . Too much / little stock. Miss out on opportunities , possible fall in profits . Loss of customer trust , loss of customers and reputation . Financial issues . Projects take longer , cost more , stakeholders unhappy . Possible project failure . Q uesto's Q uestions 2.3 - Quality of Information: 1. Describe 5 characteristics of information . [10 ] 2. Explain 5 positive impacts of good quality information . [10 ] 3. Explain 5 negative impacts of poor quality information . [10 ] 2.2 - Information Classification 2.4 - Information Management Topic List

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

A complete list of tags required for students to know how to use in the 2016 Eduqas GCSE specification. Follow the links on each tag to see how to use them. Here you can find a list of tags. Click a tag to see how to use it. Tags for Eduqas GCSE:

Learn about different categories of computer systems that can be used to access information including handheld, fixed and shared devices. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification for Unit 2 (Global Information). 1.3 - Access & Storage Devices Exam Board: OCR Specification: 2016 - Unit 2 Handheld Devices Examples of handheld devices: Handheld devices are small, light and possibly can be worn on the human body. These devices are very portable and easy to transport but their small size restricts the space for a powerful processor or high memory capacity. Handheld devices are becoming more powerful over time with extra features, storage options and network connectivity. Advantages: Light and portable so they can be easily carried on a person or in a pocket . Runs on battery power so do not need to be plugged into a power source (unless to charge) allowing for freedom of movement . Disadvantages: Low processing power due to small size and no cooling system . Relies on battery power which may not last for long. More likely to be lost, damaged or stolen . Generally small memory / storage capacity and low versatility . Smartphone Small Tablet eReader Smartwatch Portable Devices Examples of portable devices: Portable devices are larger and more powerful than handheld devices and can be carried easily in a bag. Laptops and larger tablets are the main examples of portable devices. Advantages: Light and portable so they can be easily transported in a laptop bag or small rucksack. Runs on battery power so they can work without a power outlet , such as to complete work on a train or in a library. More powerful and versatile than handheld devices. Disadvantages: Lower processing power and smaller memory / storage capacity than fixed devices like desktops. Reliant on their battery power which may only be a few hours. Laptop Large Tablet Fixed Devices Examples of fixed devices: Fixed devices are bulky devices that require a constant power connection . The most common example of a fixed device is a desktop computer which has a higher processing power and storage capacity than handheld and portable devices. Advantages: Desktop computers have the highest processing power of commercially available home / work computers and contain sufficient cooling systems to maintain temperature. Desktops and games consoles have large storage capacities and can be upgraded / expanded to even larger sizes. Desktop computers are very versatile and are powerful enough to be used for thousands of different purposes, from basic word processing and web browsing to server roles and data mining. Disadvantages: Reliant on a power outlet and cannot be transported whilst on. Heavy and difficult to move . May require additional components like a monitor. Typically more expensive than handheld and portable devices. Desktop Games Console Smart TV Shared Devices A shared device allows multiple users to access data at the same time . Cloud storage is the most common example of a shared device and is used by individuals, schools and businesses around the world through services such as Google Drive, Apple's iCloud and Microsoft's One Drive. A data centre is a dedicated building that contains computer systems - Facebook uses data centres across the globe so that their social media service can be available to users every second of the day. Database servers were explained in Unit 1 section 3.1 . Advantages: A ccessible by multiple users at the same time . For example, the database server can be accessed by employees of a bank simultaneously. Data centres allow online services to run all hours of the day and year . For example, Google uses data centres across the world to ensure their services can be accessed all of the time. Cloud storage frees up physical space for users as the storage is located (usually) on third-party servers. Cloud storage devices allow authorised users such as clients or staff members to access information or work remotely (outside of the office). Disadvantages: Shared devices are reliant on stable network connections . If a connection is lost, access to the device will be affected . Setting up shared devices within an organisation requires technical knowledge , especially for companies establishing their own cloud storage or data centre. Examples of shared devices: Cloud Storage Data Centre Database Server Q uesto's Q uestions 1.3 - Access & Storage Devices: 1. Identify the type of device that the following devices fit into: a. Laptop b. Cloud storage c. Desktop computer d. Smartphone [4 ] 2. Describe the advantages and disadvantages of using each of the 4 types of storage devices. a. Handheld devices [6 ] b. Portable devices [6 ] c. Fixed devices [6 ] d. Shared devices [6 ] 3. For the following scenarios explain which specific device (not type) which would be suitable. You must also justify your choice . a. Working on a spreadsheet on a train before work. [4 ] b. Taking a video of a penalty in a football match to upload to Twitter. [4 ] c. Working on a file with team members located across the country. [4 ] d. Playing Civilization VI on highest settings whilst listening to rock climbing podcasts in a separate tab. [4 ] 1.2 - Storage Media Topic List 1.4 - Internet Connections