Vladimir Levenshtein’s edit distance algorithm1 as a UNIX command. There’s also a C library: levenshtein(3), and a JavaScript version.
With CLib:
$ clib install wooorm/levenshtein
Or Git clone, and then:
$ make install
Usage: levenshtein <words...>
Levenshtein algorithm CLI
Options:
-h, --help output usage information
-v, --version output version number
Usage:
# output distance
$ levenshtein sitting kitten
# 3