badges

This article will tell you what you need to know about energy points and badges:

https://khanacademy.zendesk.com/hc/en-us/articles/202487710-What-are-energy-points-

Ok. the article say how the badges can be earned but whats the benefit of badges?

For me, they are motivations for you to keep learning, just like the energy points. If you want to unlock an avatar, you work hard and answer a bunch of questions in order to earn points. Same with the badges. It's super motivating to be able to look at all those badges and feel good that you learned a lot.