Okay kiddo, so James was a man who lived a long time ago when Jesus was alive. James was actually Jesus' brother!
Now, back in those days, people didn't really have last names like we do now. So James was simply known as "James, son of Joseph." Jesus was also known as "Jesus, son of Joseph." This is because they had the same dad!
Now, James wasn't always a big supporter of Jesus and his teachings. He actually thought his brother was a little bit crazy at first. But after Jesus died and came back to life (which was a big deal), James became a really important leader in the first Christian church.
He was known for being a great teacher and for always doing what was right. Some people even called him "James the Just" because he was so fair and honest.
So even though James was just a regular guy like you and me, he ended up being a really important person in history because of his connection to Jesus and his leadership in the early Christian church.