Netfilter

Netfilter is like a super helper that works really hard to keep your computer safe from bad stuff on the internet. It's like a bouncer at a party that only lets in the good people and keeps out the troublemakers.

When you're on the internet, bad people try to send you things you don't want, like viruses or spam. Netfilter makes sure those things don't get into your computer or cause any harm.

It does this by looking at all the things that are trying to come into your computer and deciding if they're okay or not. It can be like a security guard checking everyone's IDs before they can come into a club.

If something isn't okay or safe, netfilter blocks it from getting into your computer. It's like a superhero that saves your computer from harm.

Overall, netfilter is like a big umbrella that protects your computer from bad things on the internet, so you don't have to worry about them.