Servitude in Roman Law was a concept that had to do with how people could use land that didn't belong to them. Let's imagine that you have a big field with different parts of it that you don't use very often. You could let your neighbor use that part of your land if they agreed to take care of it or to help you with something else in return. You and your neighbor would sign a paper that said what each of you had to do and that would make it official.
Now imagine that your neighbor's child grows up and decides to sell their house to someone else. That person could keep using your land if they agree to do what was written in the paper. This is called a servitude, which means that even though the land doesn't belong to them, they can still use it for a specific purpose as long as they follow certain rules.
So, in Roman Law, servitude meant that someone could use part of somebody else's land for a specific purpose if both parties agreed on it and it was written down. But the person who owned the land still had the ultimate control over how the land was used and maintained.