Eco-apartheid is when people don't have the same access to resources, like clean air and enough land, depending on where they live. Imagine if there were two neighborhoods with different houses: one neighborhood has nice, modern houses with air conditioning, but in the other neighborhood all the houses are really old and run down, and there isn't enough air conditioning for everyone. That's kind of like eco-apartheid. People in one area don't get the same resources, like fresh air and enough land, as people in another area.