For those just beginning to ID woodpeckers, the similar looking Hairy & Downy can be confusing if not seen together, where their size difference can be observed. A couple of ways to tell them apart are - Downy has a much smaller bill than Hairy in relation to the size of its head. Downy also has stripes on the underside of the rectrices / tail feathers, while Hairy typically does not.
Woodpeckers have zygodactyl feet, meaning 2 toes forward and 2 toes backward. This is perfect for the birds’ vertical lifestyle, clinging to the sides of trees.
Woodpeckers also have very powerful legs and will release their feet in tandem, using their tail feathers as a spring to motivate up a tree, or use their tail feathers as a brace when descending.
Note the whisker-like feathers that protect the nostrils (base of the bill). This is a great adaptation to filter out debris when chiseling wood.