For prehistoric taxa, see text Galbuliformes Fürbringer, 1888 Nine families of largely arboreal birds make up the order Piciformes /ˈpɪsɪfɔːrmiːz/, the best-known of them being the Picidae, which includes the woodpeckers and close relatives.

In general, the Piciformes are insectivorous, although the barbets and toucans mostly eat fruit and the honeyguides are unique among birds in being able to digest beeswax (although insects make up the bulk of their diet).

Nearly all Piciformes have parrot-like zygodactyl feet—two toes forward and two back, an arrangement that has obvious advantages for birds that spend much of their time on tree trunks[citation needed].

[5][6] The number of species in each family is taken from the list maintained by Frank Gill, Pamela C. Rasmussen and David Donsker on behalf of the International Ornithological Committee (IOC).

A number of prehistoric families and genera, from the Early Eocene Neanis and Hassiavis, the Zygodactylidae/Primoscenidae, Gracilitarsidae, Sylphornithidae, and "Homalopus",[8] to the Miocene "Picus" gaudryi and the Pliocene Bathoceleus are sometimes tentatively assigned to this order.