More than five decades after Unix was created, its philosophy and code live on in Linux, macOS, and other operating systems. Its lasting influence comes from a simple approach to software—build small programs that do one thing well, work together, and communicate through text streams.

How did Unix begin? Why was C created, and why was Unix rewritten in C? This is the story of the people who created Unix and C.

The hacker culture at MIT had roots in the Tech Model Railroad Club, whose members later programmed computers including the PDP-1. This experimentation fostered the hacker ethos, leading to the development of one of the earliest and most influential computer games, Spacewar!, and the ITS. The open, collaborative nature of ITS at the MIT AI Lab, accessible through ARPAnet, significantly influenced hacker culture and laid the groundwork for the free/open-source software movement...

The origins of hacker culture reach back to early programming communities and MIT's PDP-1 enthusiasts, who created software such as Spacewar!, text editors, and music programs. Project MAC, the AI Lab, ITS, and ARPANET helped this culture spread and influence today's open-source hacker community.

Early programmers came from mathematics, science, and engineering. Margaret Hamilton and other women helped establish software as a demanding engineering discipline.