Bird homes, or nests, are structures built by birds to provide shelter and protection for their eggs and young. Nests can be made from a variety of materials, including twigs, grasses, mud, feathers, and even human-made materials such as string and plastic. Different species of birds build different types of nests, ranging from simple cup-shaped nests to elaborate woven structures. Nests are often built in trees, shrubs, or other vegetation, but some species will also build nests on the ground or on man-made structures.