Why fgrep?

[Andrew Hume]

steve wampler asks why would you ever use fgrep rather than grep?
despite the fact that he has never seen fgrep run faster than grep,
it often does run faster. that's one reason.

the more important reason is that fgrep searches for any element of
a list of literal strings, something that grep simply cannot do.
furthermore, it does it MUCH faster than egrep does. of course,
new techniques allow fgrep to run about four times faster still.