locate = find data files, programs, directories, & objects matching your search.
For example, let's say I'm searching for a file with the word "license" in the filename:
Since you usually receive quite a long list when running locate, you'll probably want to do this:
locate license | more
locate license | less
locate searches a database called slocate.db on your hard drive which is updated every night. To manually update the database, login as root & then run:
Note that locate searches by name only. To search by any other attribute, use find. To search only for commands, use whereis.