Okay, little one, Helmut Rix is a person, but he's not just any person. He was a really smart man who studied languages and linguistics. That means he liked to learn about how different people speak and how they communicate with each other.
One of the things he was really interested in was ancient languages. That means languages from a very long time ago, like when the dinosaurs were around. He studied a lot of different ancient languages, like Latin and Greek, but he was most famous for studying something called Indo-European languages.
Indo-European languages are special because they're spoken by a lot of different people all over the world. They have things in common even though they're spoken far apart from each other. Helmut Rix wanted to learn more about how these languages were related to each other.
So, he studied a lot and wrote a lot of books about how these languages were related. He made big discoveries and helped other people learn more about how languages work. He was like a detective, trying to solve the mysteries of language.
In short, Helmut Rix was a very smart man who loved studying languages, especially ancient ones, and he helped us all learn more about how they're related to each other.