Systems Software

This section explores the essentials of systems software, focusing on the role of the operating system, user interfaces, memory management, and the functions of utility software. A solid understanding of these concepts is critical to effective computer system management and security.

Systems Software

Definition: Systems software is the software responsible for managing and controlling computer hardware, ensuring applications can run effectively.

Key Types of Systems Software

Operating Systems (OS): The main software that manages computer hardware, provides an interface, and allows applications to run.

Utility Software: Tools that help maintain, optimise, and protect a computer system (e.g., encryption, backups, defragmentation).

Operating Systems and User Interfaces

Operating System (OS)

Function: Manages all hardware and software resources, acting as a bridge between the user and the computer hardware.

Examples: Windows, macOS, Linux, and Android.

Core Functions: Managing memory, files, processes, and input/output devices, as well as providing a user interface.

User Interfaces (UI)

Definition: The means by which a user interacts with a computer.

Types of User Interfaces

Graphical User Interface (GUI): Uses icons, menus, and windows for a visual and intuitive experience (e.g., Windows or macOS).

Command-Line Interface (CLI): Users interact by typing commands, offering precise control and commonly used by technical users (e.g., in Linux or Windows Command Prompt).

Touch Interface: Found in mobile devices and tablets, allowing users to interact by tapping and swiping on a touchscreen.

 Multitasking and Memory Management

Multitasking

Definition: The ability of the operating system to execute multiple applications or processes at the same time.

How it Works: The OS allocates processing time to each application, quickly switching between them to give the impression of simultaneous execution.

Memory Management

Function: Ensures that each application has enough memory to function correctly without interfering with others.

Role of OS: Allocates and tracks memory usage, moving data between RAM and storage as needed.

Virtual Memory: When RAM is full, the OS uses a section of the hard drive as temporary memory, enabling larger applications to run.

Peripherals and Drivers

Peripherals: External devices connected to the computer, such as printers, keyboards, and storage devices.

Drivers: Software that allows the operating system to communicate with hardware devices.

Function: Drivers translate OS instructions into device-specific commands, allowing seamless device integration.

File Handling

Function: The OS manages file storage, retrieval, and organisation in folders.

File Permissions: Helps to restrict or grant access to files and directories, enhancing security.

User Management

Function: Allows multiple users to access the same computer with individual accounts and customised settings.

Permissions: The OS can assign different access levels to users, controlling which files and applications they can access.

Utility Software

Purpose: Utility software is designed to help analyse, configure, optimise, and maintain the computer. These utilities often run in the background to keep the system efficient and secure.

Types of Utility Software

Encryption Software

Function: Encrypts files and data, converting it into a secure format that can only be accessed with a decryption key.

Use Case: Protects sensitive data from unauthorised access, especially on shared or portable devices.

Disk Defragmentation

Definition: The process of reorganising fragmented data on a hard disk so that files are stored in contiguous spaces.

Purpose: Improves file access speed by reducing the time the read/write head spends searching for file fragments.

Note: Primarily used on HDDs; SSDs do not benefit from defragmentation.

Data Compression

Function: Reduces the size of files, allowing more data to be stored and faster transfers over networks.

Types

Lossless Compression: Reduces file size without losing data (used for text files and software).

Lossy Compression: Permanently removes some data for higher compression ratios, typically used for images, audio, and video.

Backups

Function: Creates copies of important data to be restored in case of loss or damage.

Types of Backup

Full Backup: A complete copy of all files and data on a system.

Incremental Backup: Only new or modified files are backed up since the last backup, saving time and storage space.