(1) The process of breaking down an Internet Protocol (IP) datagram into smaller parts to match the capabilities of the physical medium over which it will be transmitted. See also defragmentation.
(2) An operating system's process of writing different parts of a file to discontiguous sectors on a computer storage medium when contiguous space that is large enough to contain the entire file is not available. When data is thus fragmented, the time that it takes to access the data may increase because the operating system must search different tracks for information that should be in one location.
(3) The separation of the index into pieces as a result of inserts and deletions in the index.