Jack Bonnell Dennis (born October 13, 1931) is a computer scientist and Emeritus Professor of Computer Science and Engineering at Massachusetts Institute of Technology. The work of Dennis in computer systems and computer languages is recognized to have played a key role in hacker culture. As a Massachusetts Institute of Technology faculty member he sponsored easier access to computer facilities at MIT during the early development of the subculture. Much of what would later become Unix came from his early collaboration with Dennis Ritchie and Ken Thompson. This collaborative and open philosophy lives on today.