design 1980–1984. Berkeley UNIX/Berkeley Software Distribution (BSD) – The Computer Systems Research Group was a research group at Berkeley that was dedicated to enhancing AT&T Unix operating system and funded by Defense Advanced Research Projects Agency. Bill Joy modified the code and released it in 1977 under the open source BSD license, starting an open-source revolution. Deep sea diving – Joel Henry Hildebrand used helium with oxygen to mitigate decompression sickness. GIMP – In 1995, Spencer Kimball and Peter Mattis began developing GIMP as a semester-long project at Berkeley. Polygraph – invented by John Augustus Larson and a police officer from the Berkeley Police Department in 1921. Project Genie – DARPA funded project. It produced an early time-sharing system including the Berkeley Timesharing System, which was then commercialized as the SDS 940. Concepts from Project Genie influenced the development of the TENEX operating system for the PDP-10, and Unix, which inherited the concept of process forking from it. Unix co-creator Ken Thompson worked on Project Genie while at Berkeley. SPICE – Donald O. Pederson develops the Simulation Program with Integrated Circuit Emphasis (SPICE) 1972. Tcl programming language – developed by John Ousterhout in 1988. Three-dimensional Transistor – Chenming Hu won the 2014 National Medal of Technology for developing the "first 3-dimensional transistors, which radically advanced semiconductor technology". Vi text editor – Bill Joy created the first Vi editor in 1976. Wetsuit – Hugh Bradner invents first wetsuit 1952. Companies and entrepreneurship Berkeley alumni and faculty have founded many companies, some of which are shown below. Berkeley has often been cited as one of the universities that have produced most entrepreneurs, and boasts its own startup incubator, Berkeley SkyDeck. Activision Blizzard, 1979 (as Activision), co-founder Alan Miller (BS) and Larry Kaplan (BA) AIG, 1919, founder Cornelius Vander Starr (Attended) Apple, 1976, co-founder Steve Wozniak (BS) Chernin Entertainment, 2009, founder Peter Chernin (BA) Coursera, 2012, co-founder Andrew Ng (PhD) eBay, 1995, founder Pierre Omidyar (Attended) Gap Inc., 1969, co-founder Donald Fisher (BS) HTC Corporation, 1997, co-founder Cher Wang (BA) Intel, 1968, co-founders Gordon Moore (BS) and Andy Grove (PhD) Marvell Technology Group, 1995, co-founders Sehat Sutardja (MS, PhD) and Weili Dai (BA) Morgan Stanley, 1924 (as Dean Witter & Co.), co-founder Dean G. Witter (BA) Mozilla Corporation, 2005, co-founder Mitchell Baker (BA, JD) Myspace, 2003, co-founder Tom Anderson (BA) Renaissance Technologies, 1982, founder James Simons (PhD) Rotten Tomatoes, 1998, founders Senh Duong