This is Jim. Jim is a serf. Jim isn't a slave, but isn't free to leave. Jim is very tired, and gets no money. He has to pay for things with chickens and extra food. Jim works for several days in a row, but he is guaranteed food, housing, land, and protection.
By the year 800, Jim and his friends are using iron tools and having horses help them plow their fields. Jim eats black bread and veggies for dinner. If Jim wants to eat meat, he will have to hunt on his lords land, which is not allowed.
Susan is a nun. She has pledged her life to the church, so she can't have riches, or a husband. She is highly educated, and continues to learn through the church. She acts as a missionary, promoting Christianity in other countries. The Church became corrupted as their wealth and power grew. Susan now has a husband, and owns land and money.
This is Tim. Tim is a knight. Tim battles other knights in castles when his boss tells him to. Tim started training to be a knight when he was seven years old. Tim's training was very strict. Tim was named a knight in the name of god.
This is Sally. Sally is a Merchant. She works with other merchants to get more money. She develops insurance plans for her goods, and starts using credit rather than cash.
This is Sally and some of her goods. Sally is taking them on a bit of the Silk Road, a very famous trade route. Then someone will take them the rest of the way, and bring her goods to places like China, or the Middle East, somewhere she could never take it on her own.