tr

Usage: tr [OPTION]... STRING1 [STRING2]

Translate, squeeze, and/or delete characters from stdin, writing to stdout.

Options:

			-c	Take complement of STRING1
			-d	Delete input characters coded STRING1
			-s	Squeeze multiple output characters of STRING2 into one character
		

Example:

			$ echo "gdkkn vnqkc" | tr [a-y] [b-z]
			hello world