grep is the name of a common utility on many Unix or unix like
systems.

Folklore says that the name represents a command that developers
''in the old days'' used to issue within their editor or other
similar program:

   g/re/p

which was a ''global {regular expression} print'' command.

Grep reads through one or more input streams (stdin or files),
searching for a string of text which represents some for of a [regular expression],
and, depending on options provided, may produce the matching
lines of input.

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[category application]