---
tags:
  - linux
  - ostep
---
Process: running program.
Program: lifeless, set of bytes stored on disk -> OS brings it into action -> it becomes a process.

Basic technique: **time sharing**. Cost: **performance**. Processes are juggled running one at a time for a short duration.
**Space sharing** divides space rather than time. E.g a disk is space shared.

**Mechanisms** are low-level methods or protocols.
A **contxt-switch**