The first bird illustrations were all hand-drawn, and many were drawn to strict scale against museum specimens, using gridlines. With the development of photography, hand-drawn models had specimens turned into photographs, which were closer to the normal morphology of birds. With the popularization of photographic equipment, especially the rapid development of digital photography, the source of bird pictures has been greatly enriched, and in recent years more and more photographic illustrated books have appeared, replacing the hand-drawn version with photographs of birds taken in the field. It is believed that with the continuous lowering of the technical threshold of photography, photographic illustrations will gradually replace hand-drawn illustrations and become the mainstream of bird illustrations.

Bird illustrations usually include the introduction of bird areas, bird-watching guides, explanations of terms, introduction of bird species, indexes and other basic content.