Feudalism

I was very confused about feudalism, and I did a lot of research on feudalism. Most of the websites, and books said that feudalism exist, even the video we watched today in class said that feudalism was a "thing". They also describe it as a relationship between hight class people and the lower class people, such as lords and the peasants, or vassals. The books, and websites describe the feudalism is like making a contract or like promise. For example: The vassals form own army, so he will promise that he will help the manor by using his army to support and fight the war or crusade. Also sometimes a knight has to make promises to lord too, they have to promise they'll fight for the lord no matter what. It also said that feudalism keeps people in order. But none of that it's true, feudalism doesn't actually exist in the Middle Ages. The word feudalism was actually invented by a scholars to describe a political system. The medieval people didn't think that they were medievals, they might just feel like they are just like us. The Middle Ages is also named it by historians in modern days. Feudalism seems not good, because it's like forcing people to give up for themselves and do something, or like taking profits from people from lower class. I am still a bit confused about the whole feudalism thing, whether it exist or not, but I guess as I read the article it said feudalism does not exist.