Apartheid was a time in South Africa when people were separated based on their skin color.
Imagine playing with your friends, but some of your friends have to sit in a different spot or aren't allowed to use the same toys as you. That's what happened in South Africa during apartheid.
The government made laws that said black people and white people (and other groups) couldn't live in the same places, go to the same schools or even use the same public restrooms.
This wasn't fair at all, and many people fought against it. Some people, like Nelson Mandela, who later became the president of South Africa, were even put in jail for trying to change things.
Finally, in the 1990s, the government realized they had to end apartheid because it was hurting so many people. South Africans came together and decided to create a new, more equal country where everyone was treated the same. Apartheid is now a thing of the past, but it's important to remember what happened so we can make sure it never happens again.