The Development of UNIX that prompted the creation of the GNU Operating System and the Linux Kernel
Kyle Smoot
Composition 1
Ms. Christine Kirsch
11/11/2010

The Development of UNIX that prompted the creation of the GNU Operating System and the Linux Kernel
Without the Massachusetts Institute of Technology (MIT), the field of Information Technology would have never seen the development of UNIX, the GNU Operating System, or the Linux Kernel.
The Development of UNIX The late 1950’s saw the rapid improvement of electronics. With this, it became apparent that computers would soon be able to time-share by switching back and forth between multiple users quickly. Fernando Corbato at the Massachusetts Institute of Technology (MIT) Computation Center led a team that created one of the first multi-user operating systems called the Compatible Time-Sharing System (CTSS) which was highly influential to the development of UNIX. (Diaz, Christopher, © 2007 ) In the 1960’s, AT&T Bell Labs, General Electric, and MIT conducted a joint research effort to build a next generation multi-user operating system called the Multiplexed Information and Computing System (MULTICS). The Bell Labs staff involved with MULTICS, including Ken Thompson, Dennis Ritchie, Joe Ossanna, and M. D. McIlroy, saw great potential in a communal environment enabled by a multi-user computer system, and they started looking for a way to preserve capability. In 1969, Thompson wrote a game on MULTICS called Space Travel that allowed users to pilot a spaceship around a simulation of the solar system and land on the planets and moons. Later that year, when it became too expensive to maintain the GE-645 computer that they were using, Bell Labs pulled out of the project. Since Bell Labs pulled out, the access to the computer that had Space Travel on it, wound down. Ken Thompson translated the game into FORTRAN on the GECOS operating system on a GE-635 computer. However, the display movement was jerky, and access to the GECOS cost $75 an hour. This led Thompson to find a little-used PDP-7 computer with a good display processor. Then, with the help of Dennis Ritchie, he ported Space Travel to the PDP-7’s assembly language using a cross-assembler running on GECOS; they then transferred the program to the PDP-7 using punched paper tapes. After learning how to program the PDP-7, Thompson, Ritchie, and Ossanna began to program the operating system that was designed earlier. After writing the file system and a set of basic utilities, they wrote a PDP-7 assembler so they could program directly on the system. By 1970, the basic elements of the operating system were in place. The problem was that it could only support one user. In light of this, Brian Kernighan jokingly named it the Uniplexed Information and Computing System (UNICS) as a pun on the acrostic MULTICS. However, when multiprocessing functionality was added a short time later, the name was changed to UNIX, which is now just a name and not an acronym for anything. In 1970, the Bell Labs team put in a scaled down request for $65K to buy one of the new line of DEC PDP-11 computers, the first of what would become an influential line of minicomputers over the next several years. They justified the request with a plan to develop some sort of useful text-processing system. They acquired the PDP-11 in late summer and they began transferring UNIX from the PDP-7. The first PDP-11 version of UNIX used a 16 KB of memory for the operating system and provided 8 KB of memory for user programs. In the spring of 1971, interest in UNIX began to grow. So instead of writing a new text-processing system, as originally proposed, Thompson and Ritchie translated the existing “roff” text formatter from the PDP-7 to the PDP-11 and made it available to the Patent Department on their new UNIX system. This practical success helped convince Bell Labs how valuable the UNIX system was. Shortly thereafter they bought the team one of the first, powerful PDP-11/45 minicomputers to continue their development. A series of progressively better versions of UNIX were then released. When the sixth version of UNIX was released in 1975, it was made available to educational and research institutions outside of AT&T. Because U.S. Federal Law prevented Bell Labs from selling products due to its status as a unique, monopoly institution, it was also made available at no cost. In the best tradition of the free software movement, the spread of UNIX to sites across the research community seeded the development of many improvements by local programmers. Some of these were incorporated in the seventh version released in 1979.
The GNU Operating System In 1984, a hacker name Richard Stallman, known as the last of the true hackers, started the influential GNU project to develop a free operating system called GNU. GNU is fully compatible with UNIX and the name stands for “GNU’s Not UNIX”, to emphasize that it is not UNIX, only like UNIX. Stallman resigned from the MIT AI Lab to start GNU. He did this so MIT could not be able to claim the copyright on the software, but the university was kind enough to let him use their computers. (History of Linux, 1996-2010) In 1985, Stallman founded the Free Software Foundation as a tax-exempt charity for the development of free software. Stallman called the inherent in the GNU GPL “free software” since it protects crucial freedoms for all users of the code. Note that “free software” does not mean it comes without a cost; in fact, every user has the right to sell a copy for a free software package. Many programs and utilities were contributed by developers around the world, and by 1991 most of the components of the system were ready. The only thing missing was the kernel.
The Linux Kernel In that same year, Linus Torvalds, a student at the University of Helsinki, had been using Minix; a non-free UNIX-like system. Linus began writing his own kernel. He started by developing device drivers and hard drive access. By September, he had a basic design that he called Version 0.01. This kernel is called Linux, short for Linus’ UNIX, was later combined with the GNU system to produce a complete free operating system. (Sobell, 2010) On October 5th, 1991, Torvalds sent a posting to the comp.os.minix newsgroup. He announced the release of Version 0.02, a basic version that still needed minix to operate, nevertheless it attracted considerable interest. The kernel was rapidly improved by Torvalds and a growing number of volunteers communicating over the internet. By December 19th a functional, stand-alone UNIX-like Linux system was released as Version 0.11. On January 5th, 1992, Linux Version 0.12 was released. This was an improved, stable kernel. The next release was called Version 0.95, to reflect the fact that it was becoming a full-featured system. After that, Linux became an underground phenomenon with a growing group of distributed programmers that continue to debug, develop, and enhance the source code baseline to this day.
Linux continued to be improved throughout the 1990’s and started to be used in large scale applications like web hosting, networking, and database serving, proving it to be ready for production use. Version 2.2, which was a major update to the Linux kernel, was officially released in January 1999. By the year 2000, most computer companies supported Linux in one way or another. The next major release was Version 2.4 in January of 2001. This release provided compatibility with the upcoming generation of Intel’s 64-Bit Itanium computer processors.
Although Torvalds continued to function as the kernel release manager, he avoided work at any of the many companies involved with Linux in order to avoid showing favoritism to any particular organization. He instead, went to work for a company called Transmeta and helped develop mobile computing solutions. He made his home at the Open Source Development Labs, which later became known as The Linux Foundation.
As you can see, without the Massachusetts Institute of Technology (MIT), the field of Information Technology would have never seen the development of UNIX, the GNU Operating System, or the Linux Kernel.

Works Cited
Diaz, Christopher. (2007 ). Introduction to UNIX/Linux. Retrieved October 4, 2010, from Books24x7: http://library.books24x7.com.proxy.itttech.edu/book/id_26251/viewer.asp?bookid=26251&chu nkid=484176164
History of Linux. (1996-2010). Retrieved October 5, 2010, from livinginternet.com: http://www.livinginternet.com/i/iw_unix_gnulinux.htm
Sobell, M.G. (2010). A practical guide to Fedora and Red Hat Enterprise Linux 5th Edition. Boston, MA: Prentice Hall.