Each of the bird’s flight feathers is attached to the wing bone. You know how a bird folds its wings to its body when it lands? And how a feather spreads out evenly when it opens its wings to fly? There is a ligiment that runs the entire way along the forward edge of the wing so the feathers spread out evenly when the bird opens its wings.
It is not only feathers that make a bird fly. They are only the most obvious. The entire bird’s body is adapted for flying—like lite and hollow bones and the way the bones are shaped to attach the muscles. Birds also have special ways of breathing to assist in powering muscles for flight. They have skeletons where much of the back bones fused as one to help keep them stable during flight. As such, their bodies are sort of football shaped. To have flexibility, they have long necks with perhaps three times as many vertebrae as us. They have no teeth, that would be too heavy. Instead they have bills made out of keratin, the same substance that their feathers are made of but arranged in a very different way.