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# What is an email filter (anti-spam)?

### Email filters against spam

An anti-spam filter is a filter that you can apply to emails to help identify spam. In short, they apply different filters to sort spam from relevant messages.

These can take the form of simple keyword filters, or more sophisticated systems such as SpamAssassin. These use a variety of different detection methods, such as white lists, DNS-based spam detection, sender reputation systems, and more.

Spam filters are essential to avoid being overwhelmed with unwanted emails. They make it easy to manage your mailbox and reduce your chances of being phished.