UNIX history

origin

UNIX began in 1969 at AT&T Bell Labs as simplified version of the MULTICS project.

multitasking: process scheduler
multiuser: accounts and permissions included
few built-in limitations: large memory; large disks and files
hierarchical file system: single directory tree; file structure only a stream of bytes; devices accessed same as files
user space shell: interactive command interpreter; script interpreter; redirection and pipes
portable: rewritten in high-level C language in 1972
open development model: anti-trust consent decree prevented sale; distributed freely (except media cost)
plain text data and configuration: universal; human readable; text processing utilities included
on-disk documentation
development tools included: compilers; assembler; linker; build tools
designed for programmers: not compromised for naive users; hard to learn, easy to use