Byzantine law was the set of rules and regulations that were used in the Byzantine Empire a long, long time ago. It was kind of like the rules that you have at home or at school, but for a whole civilization.
Now, the Byzantine Empire was a pretty big deal. Imagine if you had a really big family, but instead of just your immediate family, it was your cousins, aunts and uncles, and even your grandparents. That's how big the Byzantine Empire was, and they needed a lot of rules to keep everybody organized and safe.
The Emperor was the ruler of the Byzantine Empire, and he made the rules. But, he didn't do it alone. He had some really smart people called lawyers and lawmakers who helped him make the rules fair and just for everyone.
One of the most important things about Byzantine law was that it was written down. That means that the rules were written on paper or parchment, so everyone could read them and understand them. This was really important because it meant that people couldn't make up their own rules, and they couldn't say they didn't know what the rules were.
Byzantine law covered lots of different things. There were rules about how you could buy and sell things, how you could get married, how you could become a citizen, and how you could be punished if you broke the rules.
One of the things that was really important about Byzantine law was that it was fair. That means that the same rules applied to everyone, no matter who they were. It didn't matter if you were rich or poor, young or old, or even if you were a man or a woman, the rules were the same for everyone.
So, that's what Byzantine law was all about. It was like the family rules for a really big family, written down so everyone could understand them, and applied equally to everyone.