Stephen Gary Wozniak, also known by his nickname Woz, is an American technology entrepreneur, electrical engineer, computer programmer, and inventor. In 1976, he co-founded Apple Computer with his early business partner Steve Jobs. Through his work at Apple in the 1970s and 1980s, he is widely recognized as one of the most prominent pioneers of the personal computer revolution.
In 1975, Wozniak started developing the Apple I into the computer that launched Apple when he and Jobs first began marketing it the following year. He was the primary designer of the Apple II, introduced in 1977, known as one of the first highly successful mass-produced microcomputers, while Jobs oversaw the development of its foam-molded plastic case and early Apple employee Rod Holt developed its switching power supply.
With human–computer interface expert Jef Raskin, Wozniak had a major influence over the initial development of the original Macintosh concepts from 1979 to 1981, when Jobs took over the project following Wozniak's brief departure from the company due to a traumatic airplane accident.