Cryptozoology is a pseudoscience that aims to prove the existence of entities from the folklore record, such as Bigfoot or chupacabras, sometimes as undetected animals otherwise considered extinct, such as dinosaurs. Cryptozoologists refer to these entites as cryptids. Because it does not follow the scientific method, cryptozoology is considered a pseudoscience by the academic world: it is neither a branch of zoology nor folkloristics.
As a field, cryptozoology originates from the works of colleagues Bernard Heuvelmans, a Belgian-French zoologist, and Ivan T. Sanderson, a Scottish zoologist. Notably, Heuvelmans published On the Track of Unknown Animals (French Sur la Piste des Bêtes Ignorées) in 1955, a landmark work among cryptozoologists that was followed by numerous other like works. Similarly, Sanderson published a series of books that assisted in developing hallmarks of cryptozoology, including Abominable Snowmen: Legend Come to Life (1961).
The term cryptozoology dates from cryptozoologist circles from 1959 or before—Heuvelmans attributes the coinage of the term cryptozoology ('the study of hidden animals') to Sanderson. Patterned after cryptozoology, the term cryptid was coined in 1983 by cryptozoologist J. E. Wall in the September edition of the International Society of Cryptozoology Newsletter. According to Wall "[It has been] suggested that new terms be coined to replace sensational and often misleading terms like 'monster'. My suggestion is 'cryptid', meaning a living thing having the quality of being hidden or unknown". The Oxford English Dictionary defines the noun cryptid as "an animal whose existence or survival to the present day is disputed or unsubstantiated; any animal of interest to a cryptozoologist".
While biologists regularly identify new species, cryptozoologists focus on creatures from the folklore record and, in turn, cryptozoologists may consider any figure from folklore to be a cryptid. Most famously, these include the Loch Ness Monster, Bigfoot, chupacabras as well as other "imposing beasts that could be labeled as monsters". In their hunt for these entities, cryptozoologists may employ devices such as motion sensitive cameras, night vision equipment, and audio recording equipment. While there have been attempts to codify cryptozoology approaches, unlike biologists, zoologists, botanists, and other academic disciplines, however, "there are no accepted, uniform, or successful methods for pursuing cryptids".