Datasheet

The History of Unix, GNU,

and Linux

The Unix tradition has a long history, and Linux comes from the Unix tradition, so to understand

Linux one must understand Unix and to understand Unix one must understand its history. Before

Unix, a developer would submit a stack of punched cards, each card representing a command,

or part of a command. These cards would be read and executed sequentially by the computer.

The developer would receive the generated output after the job had completed. This would often

be a few days after the job had been submitted; if there was an error in the code, the output was

just the error and the developer had to start again. Later, teletype and various forms of timeshar-

ing systems sped up the matter considerably, but the model was basically the same: a sequence

of characters (punch cards, or keys on keyboards — it’s still just a string of characters) submit-

ted as a batch job to be run (or fail to run), and for the result to come back accordingly. This is

signiﬁ cant today in that it is still how data is transmitted on any computerized system — it’s all

sequences of characters, transmitted in order. Whether a text ﬁ le, a web page, a movie, or music,

it is all just strings of ones and zeroes, same as it ever was. Anything that looks even slightly dif-

ferent is simply putting an interface over the top of a string of ones and zeroes.

Unix and various other interactive and timesharing systems came along in the mid-1960s. Unix

and its conventions continue to be central to computing practices today; its inﬂ uences can be seen

in DOS, Linux, Mac OS X, and even Microsoft Windows.

UNIX

In 1965, Bell Labs and GE joined a Massachusetts Institute of Technology (MIT) project known

as MULTICS, the Multiplexed Information and Computing System. Multics was intended to be a

stable, timesharing OS. The “Multiplexed” aspect added unnecessary complexity, which eventu-

ally led Bell Labs to abandon the project in 1969. Ken Thompson, Dennis Ritchie, Doug McIlroy,

and Joe Ossanna retained some of the ideas behind it, took out a lot of the complexity, and came

up with Unix (a play on the word MULTICS, as this was a simpliﬁ ed operating system inspired

by MULTICS).

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