Lethwei is a sport from a country called Myanmar, which used to be called Burma. It's a lot like boxing, but with a few key differences.
In lethwei, the fighters don't wear gloves like boxers do. Instead, they wrap their hands in cloth to help protect them. This means that the punches can hurt a lot more!
Another big difference is that fighters in lethwei can use their elbows and their knees to attack their opponent. In boxing, you can only use your fists. This makes lethwei a lot more exciting to watch because there are more ways for the fighters to attack each other.
Also, just like in boxing, the fighters have to try to knock out their opponent by hitting them really hard in the head or body, or by making them fall down. When this happens, the winner is usually decided right away and the fight ends.
Overall, lethwei is a very intense and exciting sport that combines elements of boxing and martial arts. It's popular in Myanmar and in other parts of the world too, and some people even think it might become an Olympic sport one day!