Okay, so imagine you and your friends are playing a game where everyone has to run as fast as they can. But you notice that some of your friends are having trouble running as fast as the others. They're not as good at it, and they might not be able to keep up as well.
In the same way, in India, there are some people who are not as well off as others. They might not have as much money or opportunities, and so they are called "Other Backward Class" or OBC for short. This is a way to help them and make sure they have access to all the same things as other people, like education and jobs.
It's like if you were playing the running game and your teacher said "Okay, we're going to help some of you who are having trouble running. We're going to give you special shoes that help you run faster, and we're going to make sure everyone gets a chance to be the leader of the game." That way, everyone has a fair chance and can do their best.