Wait What's Chivarly?

They always say Griffindors are known for their bravery and chivarly. But really what is chivarly? That's been bugging me for some time now.

It's come to mean brave, courteous, generous, stuff like that.
But technically, it's about feudal knights which, to me, weren't very nice at all.

All right so what's feudal?

Feudalism was the name of the most common social structure in Europe during the dark ages.
(other forms are called democracy, communism, socialism, theocracy, monarchy...)
Most of the people in the feudal system were "peasants," which was just another word for slavery.
If you were born in a certain area, you were required by law to stay there all of your life and work for the Landlord. Chivalry was what they called it when the rich people were polite to each other.

I know, this is a gross oversimplification. You'll get more in History class.
Can anyone do better, short of writing a book?

Wow. That's not so good.

i thought it mean the same thing as brave

Chivalry[1] is a term related to the medieval institution of knighthood. It is usually associated with ideals of knightly virtues, honour and courtly love. The word is derived from the French word chevalier, indicating one who rides a horse (Fr. cheval).
Today, the terms chivalry and chivalrous are used to describe courteous behavior, especially that of men towards women.