A system for describing instants in time, defined as the number of seconds that have elapsed since 00:00:00 Coordinated Universal Time (UTC), Thursday, 1 January 1970, not counting leap seconds, used in Unix and many other operating systems.

Less common spelling of Unix-like

(computing) An approach to software development based on the experience of developing the Unix operating system, emphasizing the creation of minimalist, modular, extensible code that can be easily maintained and repurposed.