- It provides a user interface so that we can interact with the computer
- It manages applications that are running on the computer, starting them when the user requests, and stopping them when they are no longer needed
- It manages files, helping us save our work, organise our files, find files that we have saved and load files
- It manages the computers memory, deciding what should be loaded into memory and what should be removed
- It looks after computer security, preventing unauthorised access to the system
- It manages the computer’s input and output hardware such as printers, etc.
But, just having an operating system running alone on a computer is also not very useful - we need to have application software (such as Word, Excel, etc.) so that we can actually do useful tasks with the computer.
Useless!On its own, the hardware of a computer is a fairly useless lump of plastic and metal!
It Works!(But it's not very useful)
Add in an operating system and you have a computer that actually works.
Useful!To do any useful work you will also have to add application software.