System and application software

Classifying Software

All software can be divided into two broad categories: system software and application software. The distinction is based on the software's purpose and who or what it serves. System software serves the computer itself and the operating environment; application software serves the end user by performing specific, meaningful tasks.

This classification matters because the two types of software interact in a defined way: system software runs first and provides the platform on which application software can operate. Without system software managing the hardware and providing services, application software cannot function.

System Software and Application Software

System Software

System software is software that manages the hardware resources of a computer and provides a stable platform on which application software can run. It works largely in the background, invisible to most users, and deals directly with the physical components of the system - the processor, memory, storage devices, and input/output devices.

System software must be present and running before any application software can be loaded. It acts as the essential layer between the raw hardware and the programs that users interact with.

Examples of system software
  • Operating system (OS) - e.g. Windows 11, macOS, Linux, Android, iOS. The OS manages all hardware resources, controls which programs run and when, handles file storage, and provides a user interface. It is the most important piece of system software.
  • Device drivers - small programs that allow the OS to communicate with specific hardware devices such as printers, graphics cards, keyboards, or webcams. Each hardware component typically needs its own driver.
  • Utility software - programs that maintain, organise, or optimise the computer system, e.g. antivirus software, disk defragmenters, file compression tools, backup utilities, and task managers.

Application Software

Application software (often called simply an "application" or "app") is software designed to help the end user perform a specific, meaningful task. Unlike system software, which works in the background, application software is what users directly interact with. It depends on system software to function - the operating system must be running before any application can be launched.

Application software ranges from general-purpose tools used across many different contexts to highly specialised programs written for a single purpose.

Examples of application software
  • Productivity software - e.g. Microsoft Word (word processing), Microsoft Excel (spreadsheets), Microsoft PowerPoint (presentations). Used across education, business, and personal contexts.
  • Web browsers - e.g. Google Chrome, Mozilla Firefox, Safari. Allow users to access and navigate the internet.
  • Media players - e.g. VLC, Spotify, YouTube. Used for playing audio and video files.
  • Games - software designed for entertainment, from simple mobile games to complex 3D simulations.
  • Specialist software - e.g. Adobe Photoshop (image editing), AutoCAD (engineering design), accounting packages. Designed for specific professional tasks.

How the Two Types Relate

System software and application software form a layered structure. The hardware sits at the bottom. System software - particularly the operating system - sits above the hardware, managing it and abstracting its complexity. Application software sits at the top, relying on the OS to handle all hardware interactions. When you open a word processor, it sends requests to the OS, which coordinates the CPU, RAM, and storage on the application's behalf.

This design means application developers do not need to write code that directly controls hardware. They write to the OS's interfaces and trust the system software to handle the rest. It also means that the same application can run on different hardware configurations, provided the OS supports both.

 Key Takeaways

  • System software manages hardware resources and provides the platform on which application software runs. Examples: operating systems, device drivers, utility software.
  • Application software performs end-user tasks. Examples: word processors, browsers, games, specialist professional tools.
  • System software must be running before application software can function - application software depends on the platform system software provides.
  • The operating system is the most important piece of system software: it manages all hardware, controls running programs, and provides the interface between hardware and applications.