• UNIX was developed in the 70s at AT&T labs by Ken Thompson, and Dennis Ritchie.
• ‘C’ is the language of choice for UNIX, in fact about 90% of UNIX is written in ‘C’.
• UNIX has provided the basis for many simpler operating systems like MS-DOS. Therefore IBM PC users will notice many commands are similar
• Two major releases of UNIX currently popular are AT&T UNIX, and BSD UNIX from Berkeley, these are being replaced by Solaris.
Kernel - A set of hardware services subroutines which talk to all software programs running on the system. This helps provide device independence for programs.
Shell - An interface that accepts user input, executes and tracks user and system programs, executes batch files. Many shells are often run at the same time, this is like having many PC’s available at once.
• A very large supply of public domain software has been developed for UNIX over the last 25 years.
• Most popular languages, and packages are now available for UNIX machines.
• Most computer hardware vendors are making UNIX (or a scaled down version) fit into their computers. Some spin off versions are, SCO UNIX, XENIX, MACH, etc.
• Some of the many features of UNIX are,
- Multitasking (many programs at once)
- Multi-User (Many users at once)
- Shared Resources (disks, printers, etc)
• The features of many UNIX workstations,
- approximately 1 Gig.. local disks for swap space