The order Cuculiformes comprises birds commonly known as cuckoos, roadrunners, and anis. These birds are primarily found in tropical and subtropical regions and are categorized by their unique zygodactyl feet and highly specialized bills. The family Cuculidae encompasses most cuckoos and has several synonyms, including the order Cuculiforhynchus and the family Cuculoides. The family Crotophagidae includes anis and is often referred to as the order Crotophaginae or Crotophagiformes. Additionally, the family Geococcyxidae, which includes the roadrunner, has been classified as the order Geococcyxiformes. Despite these synonyms, the order Cuculiformes remains the most widely recognized classification for these distinctive birds.