Unix began as a low-cost Bell Labs research effort after Multics, then earned internal hardware funding and spread through universities into one of software history's highest-return corporate research investments.
Unix turned a small Bell Labs operating-system project into a durable model built around processes, files, composable tools and a portable implementation in C.
C emerged alongside Unix at Bell Labs and helped demonstrate that operating systems could be written in a high-level language without giving up close control of the machine.
Unix and C were not just successful technologies. Together they made portability, composability, and a programmer-centered environment into a durable software culture.