What is Feudalism?
The feudal system
Feudalism is a system of promises that governed the relationship between lords and vassals. Everybody, from peasants to kings is in the feudal system.
Kings and queens are all lords of every people in their nation. To able to protect themselves lords built castle, but the castle aren't built with stones but in wood.
The nobles were vassals of the kings and queens. The lords are responsible for their vassals (nobles), but if the lords break their responsibilities the nobles can break ties with them. The vassals have more responsibilities; they have to give money to the lord every time there is a special occasion. They also have to give shelter and foods to the lords every time they have to visit. A vassal could serve for two lords.
Knights served both lords (kings and queens) and nobles, for exchange of lands. Knights have to be paid in fiefs or land, since all their equipment is so expensive. If they have enough fiefs knights could be lords themselves.
Peasants have to live in a manor, a house of a knight, to work for knights but for exchange they get protection. The peasants could keep some of their items that they produce. The feudal system can be very confusing if it isn't properly organized.