History of UNIX

I. Introduction

The primary part of every computer is its operating system. It is first loaded into memory at boot-up and performs many essential functions such as providing an interface for the hardware and other software.

Many operating systems have been developed over the years. UNIX is outstanding in both its long life and strength.

II. UNIX - In the Beginning

UNIX was first formulated in the Bell Laboratories under AT&T. Its development is primarily associated with Ken Thompson and Dennis Ritchie. The reason behind its development was, remarkably enough, because Ken Thompson had developed a game called Space Travel for a mainframe OS. Mainframe time was expensive. They decided to transform the game to run on a smaller computer. But a new operating system was needed and voila! - UNIX.

The UNIX project team members established a set of guidelines to assist them in development of the system:

(i) Make each program do one thing well.

English: Ken Thompson and Dennis Ritchie being awa...

Photo of Unix creators Ken Thompson (left) and Den...

Unix

To do a new job, build afresh rather than complicate old programs by adding new features.

(ii) Expect the output of every program to become the input to another, as yet unknown, program. Don't clutter output with extraneous information. Avoid stringently columnar or binary input formats. Don't insist on interactive input.

(iii) Design and build software, even operating systems, to be tried early, ideally within weeks. Don't hesitate to throw away the clumsy parts and rebuild them.

(iv) Use tools in preference to unskilled help to lighten a programming task, even if you have to detour to build the tools and expect to throw some of them out after you've finished using them.

The first documentation of the new operating system was the "UNIX Programmer's Manual" by Ken Thompson and Dennis Ritchie. In the second edition of the manual, it was mentioned that...