COMPUTER FUNDAMENTALS | OPERATING SYSTEMS
DESIGNED FOR IB EXAMINATIONS
OBJECTIVES
A1.3.2 Describe the functions of an operating system.
• Maintaining system integrity while running operating systems’ background operations
• Memory management, file system, device management, scheduling, security, accounting, graphical
user interface (GUI), virtualization, networking
A1.3.2 Describe the functions of an operating system.
• Maintaining system integrity while running operating systems’ background operations
• Memory management, file system, device management, scheduling, security, accounting, graphical
user interface (GUI), virtualization, networking
SECTION 1 | MAINTAINING SYSTEM INTEGRITY
One of the core functions of an operating system is to maintain system integrity while running background operations. System integrity refers to the stability, reliability, and correct functioning of the computer system, even when multiple tasks and services are running simultaneously.
Background Operations in an Operating System
Background operations are tasks performed by the operating system that run without direct user interaction. These operations are essential for keeping the system functional and responsive. Examples include:
Although users may not be aware of these tasks, they are continuously running to support application software and user activities.
Maintaining System Integrity
To maintain system integrity, the operating system must ensure that background operations do not interfere with each other or with user applications. This is achieved through several mechanisms:
Importance of System Integrity
Maintaining system integrity is critical because failures in background operations can lead to data corruption, system instability, or security vulnerabilities. By carefully managing background tasks, the operating system ensures:
By supervising background operations and enforcing strict control over processes and resources, the operating system preserves system integrity and ensures that the computer functions safely and efficiently at all times.
Background Operations in an Operating System
Background operations are tasks performed by the operating system that run without direct user interaction. These operations are essential for keeping the system functional and responsive. Examples include:
- Managing system services and daemons
- Handling input and output requests
- Monitoring system performance
- Performing security checks and updates
- Managing device communication
Although users may not be aware of these tasks, they are continuously running to support application software and user activities.
Maintaining System Integrity
To maintain system integrity, the operating system must ensure that background operations do not interfere with each other or with user applications. This is achieved through several mechanisms:
- Process Isolation: Each process runs in its own protected memory space, preventing faulty or malicious processes from affecting others or the operating system itself.
- Controlled Resource Access: The operating system regulates access to hardware resources such as the CPU, memory, and storage, ensuring that background tasks do not monopolize system resources.
- Error Detection and Handling: The OS detects hardware and software errors during background operations and takes corrective action, such as terminating a process or logging errors, to prevent system crashes.
- Privilege Levels: Background system processes often run with higher privileges than user applications, but access is strictly controlled to reduce security risks.
Importance of System Integrity
Maintaining system integrity is critical because failures in background operations can lead to data corruption, system instability, or security vulnerabilities. By carefully managing background tasks, the operating system ensures:
- Reliable execution of applications
- Protection of user data
- Continuous and stable system operation
By supervising background operations and enforcing strict control over processes and resources, the operating system preserves system integrity and ensures that the computer functions safely and efficiently at all times.
SECTION 2 | MEMORY MANAGEMENT
Memory management is a fundamental function of an operating system that involves controlling and coordinating the use of main memory (RAM). Its purpose is to ensure that programs have access to the memory they need to run efficiently, while maintaining system stability and preventing interference between processes.
Role of the Operating System in Memory Management
The operating system is responsible for deciding:
Applications do not access physical memory directly. Instead, the operating system provides an abstraction that allows programs to request memory without needing to know where it is physically located.
Key Functions of Memory Management
The operating system performs several important tasks related to memory:
Importance of Memory Management
By carefully controlling how memory is allocated, protected, and reused, the operating system ensures that applications run smoothly while maintaining overall system integrity.
Role of the Operating System in Memory Management
The operating system is responsible for deciding:
- Which parts of memory are allocated to which programs
- When memory is allocated and deallocated
- How to keep programs separated from one another in memory
Applications do not access physical memory directly. Instead, the operating system provides an abstraction that allows programs to request memory without needing to know where it is physically located.
Key Functions of Memory Management
The operating system performs several important tasks related to memory:
- Memory Allocation and Deallocation: When a program starts, the OS allocates memory for its code, data, and variables. When the program finishes, this memory is released so it can be reused by other programs.
- Process Isolation: Each running process is given its own protected area of memory. This prevents one program from accidentally or deliberately accessing or overwriting another program’s data.
- Efficient Use of Memory: The OS aims to maximize the use of available RAM so that multiple programs can run at the same time without wasting memory.
- Virtual Memory: If physical memory is limited, the operating system can use secondary storage (such as a hard disk or SSD) as an extension of RAM. This allows larger or more programs to run, even if they do not all fit into main memory at once.
Importance of Memory Management
- Effective memory management is essential for system performance and reliability. Without it:
- Programs could overwrite each other’s data
- The system could become unstable or crash
- Multitasking would be inefficient or impossible
By carefully controlling how memory is allocated, protected, and reused, the operating system ensures that applications run smoothly while maintaining overall system integrity.
What is the main purpose of memory management in an operating system?
A. To control how files are stored on a hard disk.
B. To allocate, protect, and manage main memory for running programs.
C. To translate programs into machine code.
D. To manage communication over a network.
SECTION 3 | FILE SYSTEM MANAGEMENT
The file system is a core component of an operating system that manages how data is stored, organized, accessed, and protected on secondary storage devices such as hard disks and solid-state drives. It provides a structured and efficient way for users and applications to work with data without needing to understand how the storage hardware operates.
Role of the Operating System in File Systems
The operating system controls the file system and acts as an interface between storage hardware and application software. Programs do not interact with raw storage blocks directly. Instead, they use files and directories provided by the file system, which abstracts the physical details of data storage.
Key Functions of a File System
The operating system performs several important tasks related to file systems:
Importance of the File System
Without a file system, data would have to be accessed by referring to exact physical storage locations, which would be impractical and error prone. By managing files and directories, the operating system ensures:
The file system enables the operating system to store and retrieve data efficiently while hiding the complexity of physical storage devices from users and applications.
Role of the Operating System in File Systems
The operating system controls the file system and acts as an interface between storage hardware and application software. Programs do not interact with raw storage blocks directly. Instead, they use files and directories provided by the file system, which abstracts the physical details of data storage.
Key Functions of a File System
The operating system performs several important tasks related to file systems:
- File Organization: Data is stored in files, which are grouped into directories (or folders). This hierarchical structure allows data to be organized logically, making it easier to locate and manage.
- File Naming and Metadata: Each file has a name and associated metadata, such as file size, creation date, and access permissions. The operating system maintains this information to manage files correctly.
- File Access and Operations: The OS provides operations such as creating, opening, reading, writing, copying, and deleting files. These operations ensure controlled and consistent access to stored data.
- Access Control and Protection: The file system enforces permissions that determine who can read, write, or execute a file. This helps protect data from unauthorized access or accidental modification.
- Efficient Use of Storage: The operating system tracks free and used storage space, allocating space to files as needed and reclaiming it when files are deleted.
Importance of the File System
Without a file system, data would have to be accessed by referring to exact physical storage locations, which would be impractical and error prone. By managing files and directories, the operating system ensures:
- Reliable long-term data storage
- Organized and user-friendly access to data
- Data protection and integrity
The file system enables the operating system to store and retrieve data efficiently while hiding the complexity of physical storage devices from users and applications.
What is the main role of the file system in an operating system?
A. To schedule CPU time between processes.
B. To manage how data is stored, organized, and accessed on secondary storage.
C. To control network communication.
D. To translate programs into machine code.
SECTION 4 | DEVICE MANAGEMENT
Device management is a key function of an operating system that controls and coordinates the use of hardware devices connected to a computer system. These devices include input devices (such as keyboards and mice), output devices (such as monitors and printers), and secondary storage devices.
Role of the Operating System in Device Management
The operating system acts as an intermediary between application software and hardware devices. Applications do not communicate directly with devices. Instead, they make requests to the operating system, which handles the interaction in a safe and standardized way.
This abstraction allows software to work with devices without needing to understand device-specific hardware details.
Device Drivers
A device driver is a specialized piece of software that allows the operating system to communicate with a specific hardware device. Each type of device requires an appropriate driver so that the OS can send commands to the device and receive data from it.
By using device drivers, the operating system can support a wide range of hardware while providing a consistent interface to applications.
Key Functions of Device Management
The operating system performs several important tasks related to device management:
Importance of Device Management
Without device management, applications would need to include hardware-specific code, making software complex and less portable. By managing devices centrally, the operating system ensures:
Device management allows the operating system to control hardware devices effectively while hiding their complexity from users and applications.
Role of the Operating System in Device Management
The operating system acts as an intermediary between application software and hardware devices. Applications do not communicate directly with devices. Instead, they make requests to the operating system, which handles the interaction in a safe and standardized way.
This abstraction allows software to work with devices without needing to understand device-specific hardware details.
Device Drivers
A device driver is a specialized piece of software that allows the operating system to communicate with a specific hardware device. Each type of device requires an appropriate driver so that the OS can send commands to the device and receive data from it.
By using device drivers, the operating system can support a wide range of hardware while providing a consistent interface to applications.
Key Functions of Device Management
The operating system performs several important tasks related to device management:
- Device Communication: The OS controls data transfer between devices and the system, handling input and output operations efficiently.
- Resource Allocation: When multiple programs request access to the same device, the operating system manages these requests to prevent conflicts.
- Buffering and Spooling: Data may be temporarily stored in memory (buffering) or queued (spooling) to improve performance and allow devices such as printers to be shared.
- Error Handling: The operating system detects and responds to device errors, such as disconnected hardware or failed data transfers.
Importance of Device Management
Without device management, applications would need to include hardware-specific code, making software complex and less portable. By managing devices centrally, the operating system ensures:
- Reliable communication with hardware
- Efficient sharing of devices between programs
- System stability and integrity
Device management allows the operating system to control hardware devices effectively while hiding their complexity from users and applications.
What is the main purpose of device management in an operating system?
A. To manage file storage on a disk.
B. To control communication between software and hardware devices using drivers.
C. To allocate memory to programs.
D. To schedule processes for CPU time.
SECTION 5 | SCHEDULING
Scheduling is a key function of an operating system that determines how processor (CPU) time is allocated to running programs. Its purpose is to allow multiple processes to share the CPU efficiently, giving the appearance that many programs are running at the same time.
Role of the Operating System in Scheduling
The operating system controls the execution of processes by deciding:
Applications do not manage CPU access directly. Instead, the operating system schedules processes in a controlled and fair manner.
Multitasking and Time Sharing
Modern operating systems use multitasking, where the CPU switches rapidly between processes. Each process is given a small slice of CPU time, known as a time slice. This allows users to run multiple applications simultaneously without one program dominating the processor.
Scheduling Policies
The operating system may use different scheduling strategies depending on system goals, such as responsiveness or efficiency. Although the specific algorithms vary, all scheduling aims to:
Importance of Scheduling
Without scheduling:
By carefully controlling CPU access, the operating system ensures smooth multitasking, efficient processor use, and a responsive user experience.
SECTION A1.3.3 Looks further into scheduling and types of scheduling
Role of the Operating System in Scheduling
The operating system controls the execution of processes by deciding:
- Which process should use the CPU
- When a process should start or stop running
- How long a process is allowed to run before another process is given CPU time
Applications do not manage CPU access directly. Instead, the operating system schedules processes in a controlled and fair manner.
Multitasking and Time Sharing
Modern operating systems use multitasking, where the CPU switches rapidly between processes. Each process is given a small slice of CPU time, known as a time slice. This allows users to run multiple applications simultaneously without one program dominating the processor.
Scheduling Policies
The operating system may use different scheduling strategies depending on system goals, such as responsiveness or efficiency. Although the specific algorithms vary, all scheduling aims to:
- Maximize CPU utilization
- Maintain system responsiveness
- Prevent starvation, where a process never gets CPU time
Importance of Scheduling
Without scheduling:
- Only one program could run at a time
- The system would be unresponsive
- Background tasks could block user applications
By carefully controlling CPU access, the operating system ensures smooth multitasking, efficient processor use, and a responsive user experience.
SECTION A1.3.3 Looks further into scheduling and types of scheduling
SECTION 6 | SCHEDULING
Security is a critical function of an operating system that protects the computer system, its data, and its users from unauthorized access, misuse, and damage. The operating system enforces security measures to ensure that resources are accessed only by authorized users and processes.
Role of the Operating System in Security
The operating system acts as the central authority for security on a computer system. All access to hardware resources, files, and system services is mediated by the OS, allowing it to enforce security rules consistently.
Key Security Functions
The operating system provides several mechanisms to maintain security:
Importance of Operating System Security
Without effective security:
By enforcing authentication, access control, encryption, and monitoring, the operating system provides a secure foundation for all software running on the system.
Role of the Operating System in Security
The operating system acts as the central authority for security on a computer system. All access to hardware resources, files, and system services is mediated by the OS, allowing it to enforce security rules consistently.
Key Security Functions
The operating system provides several mechanisms to maintain security:
- User Authentication: The OS verifies the identity of users, typically through usernames and passwords, before granting access to the system.
- Access Control: Permissions determine what actions a user or process can perform, such as reading, writing, or executing files. This prevents unauthorized access to sensitive data.
- Encryption: The operating system may support encryption to protect data stored on disks or transmitted across networks. Encryption converts data into an unreadable form so that only authorized users with the correct key can access it.
- Auditing and Monitoring: The OS can record system activity, such as login attempts and file access, and monitor system behaviour. This helps detect security breaches and supports accountability.
- Protection Against Malware: Operating systems include mechanisms to help defend against malware, which is malicious software designed to disrupt or damage a system. This includes protection against viruses, which are programs that can replicate and spread by infecting other files or systems.
- Process Protection: Running programs are isolated from one another so that a malicious or faulty process cannot interfere with other programs or the operating system itself.
Importance of Operating System Security
Without effective security:
- Sensitive data could be accessed or altered without permission
- Malware and viruses could damage the system
- User privacy and system integrity could be compromised
By enforcing authentication, access control, encryption, and monitoring, the operating system provides a secure foundation for all software running on the system.
What is the main purpose of security in an operating system?
A. To translate high-level programs into machine code.
B. To protect the system and data using authentication, access control, encryption, and malware protection.
C. To organize files on storage devices.
D. To manage CPU scheduling.
SECTION 7 | ACCOUNTING
Accounting is a function of an operating system that involves tracking and recording how system resources are used. Its purpose is to monitor the consumption of resources such as CPU time, memory, storage, and input/output devices by users and processes.
Role of the Operating System in Accounting
The operating system continuously collects data about system activity. This information allows the OS and system administrators to understand how resources are being used and to ensure that the system operates fairly and efficiently.
Accounting is especially important in multi-user systems, servers, and shared computing environments.
What the Operating System Tracks
The operating system may record:
Uses of Accounting Information
Accounting data can be used for several purposes:
Importance of Accounting
Without accounting:
By tracking and analysing resource usage, the operating system supports efficient, fair, and accountable use of system resources.
Role of the Operating System in Accounting
The operating system continuously collects data about system activity. This information allows the OS and system administrators to understand how resources are being used and to ensure that the system operates fairly and efficiently.
Accounting is especially important in multi-user systems, servers, and shared computing environments.
What the Operating System Tracks
The operating system may record:
- CPU Usage: How much processor time each process or user consumes.
- Memory Usage: The amount of main memory used by programs.
- Storage Usage: Disk space used by files and applications.
- Input/Output Activity: Use of devices such as printers or network interfaces.
Uses of Accounting Information
Accounting data can be used for several purposes:
- Performance Monitoring: Identifying processes or users that consume excessive resources.
- System Optimization: Helping administrators adjust system settings to improve efficiency.
- Fair Resource Allocation: Ensuring no single user or program monopolizes system resources.
- Billing and Quotas: In some systems, resource usage may be used for charging users or enforcing limits.
Importance of Accounting
Without accounting:
- Resource misuse could go unnoticed
- System performance could degrade
- Fair access to shared resources would be difficult to maintain
By tracking and analysing resource usage, the operating system supports efficient, fair, and accountable use of system resources.
SECTION 8 | GRAPHICAL USER INTERFACE
A Graphical User Interface (GUI) is a function of an operating system that allows users to interact with a computer using visual elements rather than text-based commands. The GUI plays a central role in Human–Computer Interaction (HCI), which focuses on making computer systems usable, efficient, and accessible for humans.
Role of the Operating System in the GUI
The operating system provides and manages the graphical interface, controlling how visual elements are displayed and how user input is processed. It translates user actions, such as clicking or tapping, into system commands.
The GUI acts as an abstraction layer between the user and the system, enabling interaction without requiring knowledge of internal system operations.
Key Functions Supported by the GUI
The operating system’s GUI supports many everyday tasks, including:
Accessibility in the GUI
Accessibility is an important aspect of GUI design and HCI. Operating systems include accessibility features to ensure that users with different needs can use the system effectively. Examples include:
Importance of the GUI
By supporting effective human–computer interaction, the GUI makes computers accessible to a wide range of users. It enables efficient file and application management, supports personalization, and provides accessibility features that promote inclusive computing.
Role of the Operating System in the GUI
The operating system provides and manages the graphical interface, controlling how visual elements are displayed and how user input is processed. It translates user actions, such as clicking or tapping, into system commands.
The GUI acts as an abstraction layer between the user and the system, enabling interaction without requiring knowledge of internal system operations.
Key Functions Supported by the GUI
The operating system’s GUI supports many everyday tasks, including:
- File Management: Users can create, open, move, rename, and delete files and folders using visual tools such as file explorers.
- Application Management: The GUI allows users to launch, switch between, and close applications using windows, taskbars, and icons.
- Customisation and Personalisation: Users can adjust the appearance and behaviour of the interface, such as changing themes, backgrounds, layouts, and display settings to suit personal preferences.
Accessibility in the GUI
Accessibility is an important aspect of GUI design and HCI. Operating systems include accessibility features to ensure that users with different needs can use the system effectively. Examples include:
- Large Text and Display Scaling: Text and interface elements can be enlarged to assist users with visual impairments.
- Read-Aloud and Screen Readers: On-screen text can be read aloud to support users with limited vision or reading difficulties.
- Dictation and Voice Control: Users can input text and control the system using speech instead of a keyboard.
- High-Contrast Modes and Colour Adjustments: Improve visibility for users with colour vision deficiencies.
Importance of the GUI
By supporting effective human–computer interaction, the GUI makes computers accessible to a wide range of users. It enables efficient file and application management, supports personalization, and provides accessibility features that promote inclusive computing.
What is the main role of the graphical user interface (GUI) in an operating system?
A. To allocate CPU time between processes.
B. To provide a visual, user-friendly, and accessible way for users to interact with files and applications.
C. To record system resource usage for billing.
D. To protect the system using encryption.
SECTION 9 | VIRTUALISATION
Virtualisation is a function of an operating system that allows a single physical computer to run multiple isolated computing environments at the same time. Each environment behaves like a separate computer, even though they share the same underlying hardware.
Role of the Operating System in Virtualisation
The operating system supports virtualisation by abstracting hardware resources such as the CPU, memory, storage, and network interfaces. These resources are then allocated to virtual machines (VMs), which run their own operating systems and applications independently, thus aiding in load balancing.
In some systems, this role is managed directly by the operating system, while in others it is handled by a specialized layer known as a hypervisor.
How Virtualisation Works
Virtualisation creates the illusion that each virtual machine has its own:
The operating system ensures that these virtual machines are isolated from one another so that a problem in one VM does not affect others or the host system.
Benefits of Virtualisation
Virtualisation provides several important advantages:
Importance of Virtualisation
Without virtualisation, each operating system would require its own physical computer. By supporting virtual machines, the operating system enables efficient use of hardware, improves system flexibility, and supports modern computing environments such as cloud computing and server consolidation.
Role of the Operating System in Virtualisation
The operating system supports virtualisation by abstracting hardware resources such as the CPU, memory, storage, and network interfaces. These resources are then allocated to virtual machines (VMs), which run their own operating systems and applications independently, thus aiding in load balancing.
In some systems, this role is managed directly by the operating system, while in others it is handled by a specialized layer known as a hypervisor.
How Virtualisation Works
Virtualisation creates the illusion that each virtual machine has its own:
- Processor
- Main memory
- Storage
- Network connection
The operating system ensures that these virtual machines are isolated from one another so that a problem in one VM does not affect others or the host system.
Benefits of Virtualisation
Virtualisation provides several important advantages:
- Efficient Resource Use: Multiple virtual machines can share the same physical hardware, reducing waste and improving efficiency.
- Isolation and Security: Each virtual machine runs independently, which limits the impact of software errors or security breaches.
- Flexibility and Testing: Different operating systems or configurations can be run on the same machine, making virtualisation useful for software testing and development.
- Cost Reduction: Fewer physical machines are required, reducing hardware and maintenance costs.
Importance of Virtualisation
Without virtualisation, each operating system would require its own physical computer. By supporting virtual machines, the operating system enables efficient use of hardware, improves system flexibility, and supports modern computing environments such as cloud computing and server consolidation.
SECTION 9 | NETWORKING
Networking is a function of an operating system that enables a computer to communicate with other computers and devices over a network. It allows systems to share data, resources, and services efficiently and securely.
Role of the Operating System in Networking
The operating system manages all network-related activities on a computer. It provides the software support required for applications to send and receive data over networks without needing to handle low-level communication details.
Applications interact with the network through services provided by the operating system rather than directly accessing network hardware.
Networking Protocols
To enable communication, the operating system supports a range of network protocols. These protocols define rules for how data is transmitted and received. While studied in more detail later, common examples include:
The operating system implements and manages these protocols so that applications can use networking services reliably.
Key Networking Functions
The operating system supports networking by providing:
Importance of Networking
Without networking support in the operating system:
By managing networking and supporting standard protocols, the operating system enables reliable communication and connected computing environments.
Role of the Operating System in Networking
The operating system manages all network-related activities on a computer. It provides the software support required for applications to send and receive data over networks without needing to handle low-level communication details.
Applications interact with the network through services provided by the operating system rather than directly accessing network hardware.
Networking Protocols
To enable communication, the operating system supports a range of network protocols. These protocols define rules for how data is transmitted and received. While studied in more detail later, common examples include:
- HTTP (Hypertext Transfer Protocol): Used for transferring web pages and web data.
- FTP (File Transfer Protocol): Used to transfer files between computers.
- SMTP (Simple Mail Transfer Protocol): Used for sending emails.
- DHCP (Dynamic Host Configuration Protocol): Automatically assigns IP addresses and network configuration settings to devices.
- TCP (Transmission Control Protocol): Ensures reliable and ordered delivery of data.
- IP (Internet Protocol): Handles addressing and routing of data packets across networks.
The operating system implements and manages these protocols so that applications can use networking services reliably.
Key Networking Functions
The operating system supports networking by providing:
- Network Communication: Managing the sending and receiving of data between devices.
- Resource Sharing: Allowing files, printers, and internet connections to be shared across a network.
- Network Configuration: Managing IP addresses, network interfaces, and connection settings.
- Security and Access Control: Protecting data and controlling access to network resources.
Importance of Networking
Without networking support in the operating system:
- Computers would operate in isolation
- Resource sharing would be limited
- Online services and cloud computing would not be possible
By managing networking and supporting standard protocols, the operating system enables reliable communication and connected computing environments.
What is the main role of networking in an operating system?
A. To manage file storage on disks.
B. To enable communication and resource sharing using protocols such as TCP/IP.
C. To allocate memory to programs.
D. To provide a graphical user interface.
Operating System (OS) | System software that manages hardware resources and provides services for application software.
System Integrity | The stable and correct functioning of a computer system without errors, crashes, or unauthorized interference.
Background Operations | Tasks performed by the operating system without direct user interaction to support system functionality.
Memory Management | The operating system function that allocates, tracks, protects, and frees main memory for running programs.
Virtual Memory | A memory management technique that uses secondary storage to extend the apparent size of main memory.
File System | The structure and methods used by an operating system to store, organize, access, and protect data on storage devices.
Directory | A container used to organize files into a hierarchical structure.
Device Management | The operating system function that controls and coordinates communication between hardware devices and software.
Device Driver | Specialized software that enables the operating system to communicate with a specific hardware device.
Scheduling | The operating system function that decides which processes use the CPU and for how long.
Time Slice | A short period of CPU time allocated to a process during multitasking.
Security | Operating system mechanisms used to protect data, resources, and users from unauthorized access or damage.
Authentication | The process of verifying a user’s identity before allowing access to a system.
Access Control | Rules that determine what actions users or processes are allowed to perform.
Encryption | The process of converting data into an unreadable form to protect it from unauthorized access.
Auditing and Monitoring | Recording and observing system activity to detect misuse, errors, or security breaches.
Malware | Malicious software designed to damage, disrupt, or gain unauthorized access to a computer system.
Virus | A type of malware that replicates itself by infecting other files or systems.
Accounting | The operating system function that tracks and records system resource usage.
Graphical User Interface (GUI) | A visual interface that allows users to interact with a computer using windows, icons, menus, and pointers.
Human–Computer Interaction (HCI) | The study and design of how people interact with computer systems.
File Management | Using the operating system to create, organize, move, and delete files and folders.
Application Management | The control of running, switching, and closing applications within an operating system.
Customisation / Personalisation | Changing system appearance or behavior to suit user preferences.
Accessibility | Features that make a computer system usable by people with a wide range of needs and abilities.
Virtualisation | The creation of virtual machines that simulate separate computers on a single physical system.
Virtual Machine (VM) | A software-based computer that runs an operating system and applications independently.
Networking | The operating system function that enables communication and resource sharing between computers.
Protocol | A set of rules that define how data is transmitted across a network.
HTTP | A protocol used to transfer web pages and web data.
FTP | A protocol used to transfer files between computers.
SMTP | A protocol used for sending emails.
DHCP | A protocol that automatically assigns IP addresses to devices on a network.
TCP | A protocol that ensures reliable delivery of data.
IP | A protocol responsible for addressing and routing data packets across networks
System Integrity | The stable and correct functioning of a computer system without errors, crashes, or unauthorized interference.
Background Operations | Tasks performed by the operating system without direct user interaction to support system functionality.
Memory Management | The operating system function that allocates, tracks, protects, and frees main memory for running programs.
Virtual Memory | A memory management technique that uses secondary storage to extend the apparent size of main memory.
File System | The structure and methods used by an operating system to store, organize, access, and protect data on storage devices.
Directory | A container used to organize files into a hierarchical structure.
Device Management | The operating system function that controls and coordinates communication between hardware devices and software.
Device Driver | Specialized software that enables the operating system to communicate with a specific hardware device.
Scheduling | The operating system function that decides which processes use the CPU and for how long.
Time Slice | A short period of CPU time allocated to a process during multitasking.
Security | Operating system mechanisms used to protect data, resources, and users from unauthorized access or damage.
Authentication | The process of verifying a user’s identity before allowing access to a system.
Access Control | Rules that determine what actions users or processes are allowed to perform.
Encryption | The process of converting data into an unreadable form to protect it from unauthorized access.
Auditing and Monitoring | Recording and observing system activity to detect misuse, errors, or security breaches.
Malware | Malicious software designed to damage, disrupt, or gain unauthorized access to a computer system.
Virus | A type of malware that replicates itself by infecting other files or systems.
Accounting | The operating system function that tracks and records system resource usage.
Graphical User Interface (GUI) | A visual interface that allows users to interact with a computer using windows, icons, menus, and pointers.
Human–Computer Interaction (HCI) | The study and design of how people interact with computer systems.
File Management | Using the operating system to create, organize, move, and delete files and folders.
Application Management | The control of running, switching, and closing applications within an operating system.
Customisation / Personalisation | Changing system appearance or behavior to suit user preferences.
Accessibility | Features that make a computer system usable by people with a wide range of needs and abilities.
Virtualisation | The creation of virtual machines that simulate separate computers on a single physical system.
Virtual Machine (VM) | A software-based computer that runs an operating system and applications independently.
Networking | The operating system function that enables communication and resource sharing between computers.
Protocol | A set of rules that define how data is transmitted across a network.
HTTP | A protocol used to transfer web pages and web data.
FTP | A protocol used to transfer files between computers.
SMTP | A protocol used for sending emails.
DHCP | A protocol that automatically assigns IP addresses to devices on a network.
TCP | A protocol that ensures reliable delivery of data.
IP | A protocol responsible for addressing and routing data packets across networks
Open-Ended Questions – Functions of an Operating System
- Describe what is meant by system integrity and explain how an operating system maintains it while running background operations.
- Explain the role of memory management in an operating system and why it is essential for multitasking.
- Describe how a file system organizes and protects data stored on secondary storage devices.
- Explain the purpose of device management and the role of device drivers in an operating system.
- Describe how scheduling allows multiple programs to share the CPU efficiently.
- Explain how operating system security protects users and data, referring to authentication, access control, and encryption.
- Discuss the role of accounting in an operating system and explain why it is important in multi-user systems.
- Explain how a graphical user interface (GUI) supports effective human–computer interaction, including accessibility features.
- Describe how virtualisation allows multiple operating systems to run on a single physical machine and state one benefit of this.
- Explain the role of networking in an operating system and briefly describe the purpose of at least two networking protocols
COMING SOON
A1.1 COMPUTER HARDWARE AND OPERATION
☐ 1.1.1 FUNCTIONS OF THE CPU
☐ 1.1.2 ROLE OF THE GPU
☐ 1.1.3 CPU VS GPU
☐ 1.1.4 PURPOSE AND TYPES OF PRIMARY MEMORY
☐ 1.1.5 FETCH, DECODE AND EXECUTE CYCLE
☐ 1.1.6 PIPELINING IN MULTICORE ARCHITECTURES
☐ 1.1.7 SECONDARY MEMORY STORAGE
☐ 1.1.8 CONCEPTS OF DATA COMPRESSION
☐ 1.1.9 CLOUD COMPUTING
A1.2 DATA REPRESENTATION AND COMPUTER LOGIC
☐ 1.2.1 REPRESENTING DATA
☐ 1.2.2 HOW BINARY IS USED TO STORE DATA
☐ 1.2.3 LOGIC GATES
☐ 1.2.4 TRUTH TABLES, CIRCUITS, EXPRESSIONS AND K MAPS
☐ 1.2.5 LOGIC CIRCUIT DIAGRAMS - COMING SOON
A1.3 OPERATING SYSTEMS AND CONTROL SYSTEMS
☐ 1.3.1 ROLE OF OPERATING SYSTEMS
➩ 1.3.2 FUNCTIONS OF OPERATING SYSTEMS
☐ 1.3.3 APPROACHES TO SCHEDULING
☐ 1.3.4 INTERUPT HANDLING
☐ 1.3.5 MULTITASKING
☐ 1.3.6 CONTROL SYSTEM COMPONENTS
☐ 1.3.7 CONTROL SYSTEM APPLICATIONS
☐ 1.1.1 FUNCTIONS OF THE CPU
☐ 1.1.2 ROLE OF THE GPU
☐ 1.1.3 CPU VS GPU
☐ 1.1.4 PURPOSE AND TYPES OF PRIMARY MEMORY
☐ 1.1.5 FETCH, DECODE AND EXECUTE CYCLE
☐ 1.1.6 PIPELINING IN MULTICORE ARCHITECTURES
☐ 1.1.7 SECONDARY MEMORY STORAGE
☐ 1.1.8 CONCEPTS OF DATA COMPRESSION
☐ 1.1.9 CLOUD COMPUTING
A1.2 DATA REPRESENTATION AND COMPUTER LOGIC
☐ 1.2.1 REPRESENTING DATA
☐ 1.2.2 HOW BINARY IS USED TO STORE DATA
☐ 1.2.3 LOGIC GATES
☐ 1.2.4 TRUTH TABLES, CIRCUITS, EXPRESSIONS AND K MAPS
☐ 1.2.5 LOGIC CIRCUIT DIAGRAMS - COMING SOON
A1.3 OPERATING SYSTEMS AND CONTROL SYSTEMS
☐ 1.3.1 ROLE OF OPERATING SYSTEMS
➩ 1.3.2 FUNCTIONS OF OPERATING SYSTEMS
☐ 1.3.3 APPROACHES TO SCHEDULING
☐ 1.3.4 INTERUPT HANDLING
☐ 1.3.5 MULTITASKING
☐ 1.3.6 CONTROL SYSTEM COMPONENTS
☐ 1.3.7 CONTROL SYSTEM APPLICATIONS
