Bukkit

• smell (simple match - will match smell either on it's own or in a sentence, not smelly)
• bu+?m (will match bum or buuuuum or any number of "u"s in the word)
• you are smelly (phrase match - will match you are smelly, not you or are or smelly on their own)
• \w*?poop\w*? (substring match - will match poop or poophead or motherpooper)
• idiot:silly (substitution, all instances of idiot will be replaced with silly)

These are examples of regular expressions, they are very powerful tools for pattern matching. For more information, look here

In the config file, it is possible to substitute a banned word or phrase for a less offensive alternative. For instance, the example below would replace all instances of the word "bum" with the word "bottom":

bum:bottom

The following example would replace all instances of the phrase "You are stupid" with the phrase "You are silly":

You are stupid:You are silly