Couple cage birds on a branch with halo and light spot background

[or may refer to:MathematicsVector space, an element in the spaceVector (spatial), in physics and engineering, an object that has a special relationship to the spatial coordinates/directionsProbability vector See more at Wikipedia.org...]

>For other uses, see Bird (disambiguation). Many - see section below. Birds are bipedal, warm-blooded, egg-laying vertebrates characterized primarily by feathers, forelimbs modified as wings, and hollow bones. Birds range in size from the tiny hummingbirds to the huge Ostrich and Emu. Depending on taxonomic viewpoint, there are about 8,800–10,200 living bird species (plus about 120–130 that have become extinct in the span of human history) in the world, making them the most diverse class of terrestrial vertebrates. See more at Wikipedia.org...