A toad can refer to a number of species of amphibians in the order Anura. A distinction is often made between frogs and toads by their appearance, prompted by the convergent adaptation among so-called "toads" to dry habitats. Many "toads" often have leathery skin for better water retention, and a brown coloration for camouflage. They also tend to burrow. However, these adaptations are not reliable indicators of its ancestry. Because taxonomy reflects only evolutionary relationships, any distinction between frogs and toads is irrelevant to their classification.
For instance, many members of the frog families Bombinatoridae, Discoglossidae, Pelobatidae, Rhinophrynidae, Scaphiopodidae, and some species from the Microhylidae family are commonly called "toads". However, the only family exclusively given the common name "toad" is Bufonidae, or the "true toads". Some "true frogs" of the genus Rana have also adapted to burrowing habits, while a bufonid species in the genus Atelopus are conversely known by the common name "harlequin frogs".
The Moche people of ancient Peru worshipped animals and often depicted toads in their art. To Vietnamese people, toad is the uncle of the Sky. According to a Vietnamese ancient story, whenever toads grind their teeth, it is going to rain.
It is commonly believed that physical contact with a toad can cause warts on humans. Warts are, in actuality, caused by an internal viral infection; thus, a toad could not possibly cause a wart. The paratoidal glands, which toads use to secrete poison for protection, are often mistaken for warts. This misconception could very conceivably have brought about such a superstition.