UNIX, a Wrinkle in Time

Dennis Ritchie and Ken Thompson are the two key people who are recognized as inventing the operating system known as Unix. They along with several other people, including Brian Kerninghan, Rob Pike and Doug McIlroy, at Bell Labs were integral to its development, design, growth and success. Peter Newmann also gets some praise as the person responsible for giving Unix its name, since it didn't even have a name for the first year after it was invented.

Dennis Ritchie was also one of the key inventors of the programming language C. C was written from a language that was previously created by Ken Thompson that was, curiously enough called B. Dr. Thompson and Dr. Ritchie had also worked on another previous project together called Multics. Multics was one of the inspirations for Unix. Combined with the best parts of other operating systems of the day these systems were put together to created Unix.

Dr. Ritchie is the only remaining member of the group today who still works at Bell Labs. He likes to point out that he had a lot of help with the Unix project and believes that he's not special and anyone else would have done the same thing in his place. Bjarne Stoustrup, who later worked with Dr. Ritchie and designed C++ says, "If Dennis had decided to spend that decade on esoteric math, Unix would have been stillborn."

In the Beginning

In 1969 Dr. Ritchie and Dr. Thompson had began creating Unix using parts of other operating systems, including one that they had worked on together called Multics, Unix was first booted up in 1971. At first it was a very basic program and lived on a very basic computer, a PDP-7 (which by the way only had 8kb of memory, a hard disk smaller than a megabyte and costs $72,000). The first program to run on it was a game, believe it or not, called "Space Travel".

They, of course, wanted to create a way to make Unix portable, or available on more than just one type of computer. The problem was that Unix was written in machine language and almost every computer of the time used its own operating system. This meant that they had to rewrite Unix for that particular computer every time they wanted to port it.

The breakthrough came with the invention of C. In 1973 they took the newly created C programming language and rewrote Unix with it, except for the kernel. Now all they had to do to port it to another computer was write a compiler for each computer they wanted to port Unix to and almost any computer could use it, as long as it had enough memory. To show it could be done they successfully moved Unix to a PDP-11.

The Tools

Different scientists added different software to Unix, each making Unix a little better in return. Unix was exactly what they wanted and needed at Bell Labs, a project they could work on and add to at will, whenever they had a thought. They created what they called "tools".

Each tool did something different and helped them achieve what they wanted out of an operating system, a program that could think for them. They created and they debugged to their hearts content to create what they considered to be the perfect operating system.

Why Unix Spreads Like Wildfire

Way back in 1958 AT&T (the previous Bell Labs) was hit with a court order requiring that they share any and all non-telephone technology to "anyone" who asked. This caused Unix and C both to be copied and dispersed rather quickly once word got out. Bell Labs began selling copies to universities for a small fee in the early 70's.

Now that the universities had their hands on this operating system, for such a low cost, they were able to teach it to their students. Soon there were graduates going out into the work force with the knowledge of this "advanced" operating system and the means to use it. This caused the business' they were working for to start using Unix, since their IT people were skilled in how to use it.

Competition

One of these universities, Berkeley in California, released its own version of Unix in 1977. This version of Unix was invented by two students named Bill Joy and Chuck Haley. With funds from DARPA the Berkley version of the operating system, known as BSD Unix, continued to grow. Soon Berkley developed networking software for Unix so that Unix computers could be connected. Then they connected Unix to LAN's.

Next was Linux. Invented by a student in Finland named Linus Torvalds in 1991 Linux is still used as a main stream operating system today and is growing in popularity each year. What makes Linux so popular is the same thing that made Unix so popular, it's ease of circulation. Anyone can use it and anyone can code it for free.

Linux is what's called "open source". This means than anyone can help work on the code, and a lot of people do. There are many different versions of Linux on the Net for people to download and use or download and code. There are also many "accessories" or "add ons" for Linux that programmers have created. If you have Linux use these add ons to make your Linux do different things or act in different ways or even look different. If you don't like what you see, change it.

Other Marketers

By 1973 there were already places outside of Bell Labs that were using the Unix software. Most were either AT&T or Western Electric. After Thompson and Ritchie wrote a paper about Unix the number became even greater. Places from all over the world were suddenly acquiring and using Unix on their systems.

Bell Labs was not allowed to market Unix, or C, themselves. This was due to the court order mentioned earlier in this paper. Still the demand for the software kept going up and up. 1977 found Unix with more than 500 copies of it running around the world, 125 of those at universities.

Modern Unix

Unix is the operating system most businesses use for their high end processors. Similarly, Unix is still used at many universities and other educational institutions. In the research community Unix is used because it can be so easily modified to meet the needs of the particular user. Unix can be used on nearly any computer anywhere in the world and still use a common interface.

Millions of copies of Unix are run today. It's become very popular in business mainly because it's so popular in the universities. If that's what the student know then that's what they're going to want to use when they go out into the real world. The flexibility of the system helps too.