western martial arts (wrestling, boxing) are focused on competition. You know how good somebody is by how they compete. Bjj was created for self defense. In self defense martial arts you show how good you are by your belt.

Q: How come there are no colored belts in boxing?

A: Boxing is a western martial art. Belts only exist in mostly but not all eastern martial arts, such as Karate, Tae Kwon Do, for basic examples.

Q: How do you know who knows what if no one has colored belts?

A: You fight them.

The WBC belt is often referred to as "The big Green Belt" and I think the WBO female title is pink

We get title not belts.

I only know Brazilian jiu jitsu. I love it because is so straight forward, there's nothing hidden.

To earn a blue belt, you need to master the 36 basic techniques. If someone has a blue belt, I know which techniques the person is familiar with.

If a guy has a purpler belt, I know what techniques he knows, and which ones he's learning.

I don't about other martial arts such as karate and others. But BJJ is very clear on what you need to learn on each rank.

When it comes to boxing, I'm sure there are moves and techniques that boxers need to learn and master.

How do you know who knows what if no one has colored belts?