What is a feather?

   A feather is a plumed quill that grows as an appendage from the skin of a bird. Most birds have many feathers that cover their bodies. The feathers of a bird are called its plumage.
   A feather consists of a central shaft with a web on each side. The shaft is stiff and hard but somewhat flexible. It emerges from the skin just as a hair does. The web is composed of a row of regularly arranged fibers, called barbs. On most feathers the web is longer on one side of the shaft than on the other. The webs of some feathers are soft and fluffy, and those of others are stiffer.
   The structure of a feather is similar in some ways to that of a scale of a fish, despite their apparent differences. Zoologists think that the feather may have evolved from some scale like appendage possessed by an ancestor of the bird.