Woodpeckers are part of the family Picidae. Members of this family are found worldwide, except for Australia, New Guinea, New Zealand, Madagascar, and the extreme polar regions.

The majority of woodpecker species feed on insects and other invertebrates living under bark and in wood, but overall the family is characterized by its dietary flexibility, with many species being both highly omnivorous and opportunistic. The diet includes ants, termites, beetles and their larvae, caterpillars, spiders, other arthropods, bird eggs, nestlings, small rodents, lizards, fruit, nuts and sap. Many insects and their grubs are taken from living and dead trees by excavation. The bird may hear sounds from inside the timber indicating where it will be productive to create a hole.

Ecologically, woodpeckers help to keep trees healthy by keeping them from suffering mass infestations. The family is noted for its ability to acquire wood-boring grubs from the trunks and branches, whether the timber is alive or dead. Having hammered a hole into the wood, the prey is extracted by use of a long, barbed tongue. They are often called the forest doctors.

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