Almost identical to the Hairy Woodpecker, the Downy Woodpecker has black spots on the tail, whereas the Hairy Woodpecker has none. One of the most handsome birds to visit my back yard.

Update:
Scientists say the Downy and the Hairy Woodpeckers are not closely related at all! It's a bizarre case of convergant evolution. No one knows what advantages it gave either bird to look so similar.