How did strategy and technology combine to create the culture of the knight

The technology that allowed the knight to be able to protect his lord is the saddle and the stirrup. These two pieces of equipment were strategically made so that the knight will not fall off the horse. When the knight is fighting an enemy or an army of enemies, he will be at a great advantage when he is atop a horse because he will be hard to reach. The problem here is what if he falls off? So the technology of the saddle and stirrup makes it possible for a knight to stay on his horse even if the horse is moving at a high speed.