PlayInfoBox

Home /Utilities /What Is a Spam Filter? Blocklists, Allowlists, and False Positives

What Is a Spam Filter? Blocklists, Allowlists, and False Positives

Tap a term to see its explanation.

What is a spam filter?

A feature that automatically screens out unwanted email β€” advertising and phishing messages, for example β€” sorting it into a separate spam folder instead of your inbox.

Blocklist (blacklist)

A list of specific senders or domains you block directly, so mail from those addresses is automatically treated as spam.

Allowlist (whitelist)

A list of trusted senders registered in advance so the spam filter never mistakenly flags them, ensuring their mail always lands in your inbox.

Phishing email

A fraudulent message that impersonates a bank or institution to try to steal personal or financial information β€” exactly the type of message spam filters work hardest to catch.

False positive

When a legitimate email gets misclassified as spam β€” a good reason to check your spam folder occasionally so you don't miss anything important.

Found an important email in your spam folder?

False positives happen occasionally, where a legitimate message gets misclassified as spam. Adding the sender to your allowlist prevents that mistake from happening again and keeps their messages reliably landing in your inbox going forward.

Curious about cybersecurity terms more broadly?

If you want to learn more about avoiding phishing emails specifically, a broader guide to cybersecurity terminology is worth exploring too.

Frequently Asked Questions

How often should I check my spam folder?

Most spam folders automatically delete their contents after a set period, so checking in periodically is worth doing if you don't want to risk missing something important.

What happens when I report something as spam?

Reporting a message as spam doesn't just route that sender's future mail to your spam folder automatically β€” it also helps improve spam filtering performance across the entire email service.