Software classification
Software splits into two broad camps: system software (runs the computer) and application software (does useful work for the user). Most exam questions ask you to classify, name examples, and explain the OS's main jobs.
System software
System software supports the computer itself. Without it, the hardware is unusable. The two main kinds are:
Operating system (OS)
The OS manages every shared resource and provides a layer between hardware and applications. Examples: Windows, macOS, Linux, Android, iOS, Chrome OS.
Main jobs of an OS:
- Process management — starts, schedules and stops programs.
- Memory management — allocates RAM to programs; uses virtual memory when RAM is full.
- File management — organises files and folders on storage.
- Peripheral management — talks to keyboard, mouse, printer, etc., via drivers.
- Security and user management — accounts, passwords, file permissions.
- User interface — GUI or CLI for the user to interact with the system.
Utility software
Utilities perform housekeeping tasks. Examples:
- Antivirus / antimalware.
- Encryption software.
- Defragmentation (rearranges file fragments on a magnetic disk for faster access).
- Compression / archive tools (ZIP, 7-Zip).
- Backup software.
- System monitor / task manager.
Utilities are sometimes counted as part of the OS but technically they are separate programs invoked when needed.
Application software
Apps perform tasks the user cares about — productivity, entertainment, communication. Examples:
- Word processors (Microsoft Word, Google Docs).
- Spreadsheets (Excel).
- Web browsers (Chrome, Firefox, Safari).
- Email clients.
- Image editors (Photoshop, GIMP).
- Games.
- Streaming apps (Netflix, Spotify).
A computer can run with no application software (uncommon) but needs system software to function at all.
Comparison
| Feature | System software | Application software |
|---|---|---|
| Purpose | Run the computer | User tasks |
| Required? | Yes (OS) | Optional |
| Direct hardware access | Often | Rarely (through OS) |
| Examples | OS, drivers, utilities | Word, Chrome, Spotify |
How they connect
Layered model from hardware up:
USER
↓
Application software ← Word, Chrome, etc.
↓
Operating system ← schedules CPU, RAM
↓
Drivers ← translate to hardware
↓
HARDWARE
Applications request services through OS APIs (system calls). The OS manages the request and forwards low-level instructions to the hardware via drivers.
✦Worked example— Worked example — classify
For each, state system or application:
- Microsoft Word — application.
- Disk Cleanup — system (utility).
- Linux kernel — system (OS).
- Chrome — application.
- Bluetooth driver — system (utility/driver).
- Spotify — application.
⚠Common mistakes— Pitfalls
- Calling utilities applications. A defragmenter helps the system, not the user's task — system software.
- Forgetting the OS itself is software. It runs on the hardware just like apps.
- Confusing firmware with the OS. Firmware controls a specific device (BIOS, printer firmware); the OS manages the whole system.
- Listing drivers as hardware. Drivers are software that control hardware.
- Treating "app" as a separate category. "App" is just colloquial for application software.
Why this matters
Knowing the boundary helps with:
- Security — system software with elevated privileges is the highest-value target.
- Updates — OS updates require restart; app updates rarely do.
- Troubleshooting — slow PC? OS issue (drivers, updates) vs app issue (browser tab leaking memory).
➜Try this— Quick check
Classify each as system or application:
- Antivirus — system (utility).
- Calculator — application.
- File Explorer — application and part of the OS shell — accept either with reasoning.
- macOS — system (OS).
- VLC media player — application.
- Disk encryption tool (BitLocker) — system (utility).
AI-generated · claude-opus-4-7 · v3-deep-computer-science