Sun Microsystems was founded in 1982 by a group of Stanford graduate students, most notably Andy Bechtolsheim, who created the original 68000 Unix system from spare parts, chewing gum, and nerd sweat.

The company's name comes from the initials of the Stanford University Network project and was initially in the business of building server-centric hardware. Since then it has made many acquisitions and moved into the software and operating system business as well, and of course created the Java Platform in the early 1990s.

Sun has a long history of involvement with Open Source, and according to a report prepared for the European Union by UNU-Merit (an institute that provides insight into the socio-political and economical factors that guide technology changes), Sun is the largest corporate contributor to open source in the world, exceeding the total of the next five largest contributors. In addition to its software contributions, the company has also offered up its operating system, Solaris and created the OpenSolaris community.

Sun set up a specific open source office in mid-2005, formalizing a direction they'd already been taking. At the time, Simon Phipps told CNet that the company was heading toward a future "where all its software is going to based on open source." This is not to say the company hasn't faced some challenges when it comes to open source software. When it worked on making Java open source in 2006, many were skeptical, and with good reason. An InfoWorld article at the time quoted a former Sun employee as saying the move flew in the face of "an old guard of middle managers who have opposed open sourcing Java." Understandably, this has led to a mixed reputation in the open source community, as evidenced by this open letter to Sun from the Apache Software Foundation.