Moderation

By checking this option, comments will not be visible on the gallery until you have validated them. Moderated comments will be in "pending" status, and you will need to activate them in the Comments section.

You can be notified by email for each new comment pending validation by activating the corresponding notification in the "Options" section of your profile page.

Moderation does not apply to administrators.

Anti-flood

The anti-flood feature lets you set the length of time after a comment has been posted that a user cannot post another comment.

Maximum number of URLs

By banning URLs altogether (0) or severely restricting them (1), you can block a large number of spam messages containing one or more URLs.