What are the peculiarities of bird beaks and legs?

There are about 8,000 species of birds and most birds perform most of their purposes, and meet many of their needs with their beaks.The forms, sizes and lengths of these beaks (usually measured from the tip to the base of the front) vary according to those purposes and needs. The most important of which are: fetching and picking up food, building nests, feeding chicks, means of defense, cleaning feathers, and softening it.

The beak is composed of a horny material, and its shape varies from one group of birds to another, the shape of the bird’s beak is adapted (ie compatible) to its diet.
The bird has two legs covered with scales, the birds’ legs are characterized by a variety of forms, and the shape of the legs of the bird is also compatible, as a beak, with his diet.