HELP!! need grep command that search all directories !

[Nasser Abbasi]

Hi,

Does any one knows how to search for a string in a file, but
have it search all files not just in current directory, but
also the whole tree under the current directory?

$find , for example searches for a file starting from a root
and traverse the whole subtree.

$grep , search for a string in files in current directory.

I need to way to combine boths, so that I can locate a string
in any file anywhere.

Any one has written something like this?

The above can very easily be done in Win95 and OS/2 with some
of the tools that come with them, SURLEY there is a way also
to do this in Unix ??

Please send me email also if you can .

thanks!
Nasser