The friend zone is when you have feelings for someone, and you want to be more than just friends, but they see you only as a friend. It's like being stuck in a special zone where you can't get out of your friendship, even if you really want to.
It's just like when you have a really good friend at school, but you don't want to date them, that's the friend zone. It can be sad and frustrating when you have romantic feelings for someone and they don't feel the same way about you.
It's important to remember that people cannot control who they are attracted to, and sometimes, it's just not meant to be. But that doesn't mean you can't still have a great friendship and enjoy each other's company.