A Bref history of Open Source Projects and Licenses
The open source software movement traces its history to the formation of the Free Software Foundation ("FSF") in 1983. The FSF was formed with the goal of creating a free version of the UNIX operating system. The FSF released a series of programs in source code form under "GNU" name ("GNU" is an irreverent acronym that stands for Gnu’s Not Unix). The GNU project did not actually result in a free version of UNIX, but did result in the creation of some popular tools for UNIX programmers, including the GNU C compiler and text editor. It also set the stage for even more ambitious free software development projects in the 1990s.
The license agreement that accompanied the GNU software -- known as the General Public License ("GPL") or "copyleft" license -- was revolutionary for its time. It is written in a non-legalistic style with a breezy preamble and statement of purpose. The GPL gives licensees broad rights to sell, copy and modify licensed programs, so long as licensees grant to downstream licensees the same rights to sell, copy and modify the modifications to the original program. Licensees are also required to make their changes available in source code form.
For many years, the FSF filled a relatively small niche in a large and growing market for proprietary products from large companies. Many UNIX programmers used -- and continue to use -- the GNU C compiler and debugger from the FSF to create new programs targeting variants of the UNIX operating system offered by companies like IBM, Hewlett-Packard and Sun.
With the Internet’s rise in the 1990s, there has been renewed interest in free software and a shift in development resources from esoteric development tools to products and technologies having a broader commercial appeal. In 1998, a group associated with free software introduced the term "open source" to emphasize a break with the pro-hacker, anti-business past associated with GNU and other free software projects and to place a new emphasis in the community on the possibilities of extending the free software model to the commercial world. These new "open source" projects would exist in the mainstream of the commercial software market and include operating systems, such as Linux, the Apache web server, and the Mozilla browser.
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