Traditional Operating System Services

CPU scheduling:

distribute or apportion computing time among several processes (or tasks) which appear to execute simultaneously.

Memory management:

divide and share physical memory among several processes.

Swapping:

move processes and their data between main memory and disk to present the illusion of a bigger machine.

I/O device support:

provide specialized code to optimally support device requirements.

File system:

organize mass storage (on disk) into files and directories.