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Give a brief introduction to UNIX.

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#RHL-1.1

1. Give a brief introduction to UNIX.

Ans. 
1. In 1969, Ken Thompson, Dennis Ritchie and the researchers at AT&T bell laboratories developed the UNIX Operating system.

2. They designed the system for the needs of a research environment, designing it run on a minicomputers.

3. UNIX was an affordable and efficient multiuser and multi-tasking operating system.

4. UNIX gradually grew from one person’s tailored design to a standard software product distributed by many different vendors, such as Novell and IBM.5. Throughout the 1970’s Bells lab began issuing official versions of UNIX and licensing the system to different users.

6. Berkeley added many new features to the system that later became standard in 1975 Berkeley released its own version of UNIX known by its distribution arm, Berkeley Software Distribution (BSD).

7. This BSD version of UNIX became a major contender to the AT&T bell lab’s version called ‘system3’, this was later followed by ‘SystemV’, which became a supported commercial software product.

8. In 1983, Berkeley released a powerful version of UNIX called BSD release 4.2, this release included sophisticated file management as well as Internet network protocols- the same protocols are now used for internet.

9. Several other companies like IBM, Harvard Packard created their own standard versions of UNIX.10. Two commercial standard versions of UNIX existed then the Open software foundation (OSF) and SystemV.
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