Unix

Operating Systems Demystified: From Kernels to Shells An operating system (OS) is the software that makes a computer usable. It coordinates hardware, runs programs, and keeps things organized and safe. A simple model divides the OS into two parts: the kernel and user space. The kernel acts as the traffic manager. It schedules the CPU, manages memory, and talks to devices. User programs—your editor, the browser, and the shell—run in user space and ask the kernel to do work via system calls. ...