The Phonetic filter module provides a profanity filter and is an improvement of the WordFilter module which compares an admin generated list of unwanted words against user submited content, e.g. comments.
Phonetic filter goes a step further by including the phonetic characteristics in the comparison as well as a list of profane words. Should a malicious user could try a variation of the cursed word, so as long as the word "sounds" like the unwanted word it will be replaced by the masking character.
It provides also a whitelist to allow certain words which sounds like unwanted. Its very lightweight and has no need for any additional tables.
If you re asking yourself why I don't consider to patch the WordFilter module instead of creating a new project please read this thread: