Wordfilters are scripts that change one word or phrase into another. They are generally used to censor words considered inappropriate by the operators of a message board or chatroom. Since they're automatic, they relieve administrators or moderators of the task of constantly patrolling every post to inspect its content.
Wordfilters can also add humor to a board (for instance, making a word like "car" become a nonsense word like "wobbly-woop!"). They can be abused, and are something a hacker might change when tampering with a board.
A good example of wordfilter using society is 4chan. The filters there are mainly used to make posts funnier and may change their meaning (like changing 'FTW' to 'sucks'). 4chan (Japanese: Yotsuba, lit. ... See also: Emoticon This list is incomplete; you can help by expanding it. ...