In computer science, an execute in place (XIP) filesystem is one that allows certain sections of programs to be stored read-only in an area other than main system memory. This is often used to allow code to run from the same location at which it is permanently stored.
For systems with small amounts of computer memory, execute in place support can mean that many instances of a large program can co-exist, as each is only using system RAM for their stack (computing), BSS, and data (computing) segments, and sharing a single read-only text segment.