Filtering Messages via list of keywords & flooding
or can set some security features in order for users to avoid from being kicked or banned in a channel accidentally or intentionally.

ex.
using of foul words
flooding the channel
advertising
etc.

this is important in an oraganization/establishment such as internet cafes. specially when they use only one (1) Internet IP for all the stations/PC. with this settings the ip will less likely to be banned.