There are different ways by which birds build their nests. For example, weaver bird selects three broad leaves one for bottom, two for top and sides and collects threads to make its nest by stitching these three leaves. Hummingbirds build on top of tree branches, using plants, soft materials and spider webs. Ravens and falcons, use cliffs, they build stick nests in the crevices. Some of the birds build their nest only with leaflets.