The Loch Ness Monster (Nessiteras rhombopteryx) is an alleged animal, identified neither as to a family or species, purportedly inhabiting Scotland's Loch Ness. The Loch Ness Monster is one of the best-known animals studied by cryptozoology. Popular belief and interest in the animal have waxed and waned over the years since it came to the world's attention in 1933. Evidence of its existence is largely anecdotal, with minimal, and much disputed, photographic material and sonar readings: there has not been any physical evidence (skeletal remains, capture of a live animal, definitive tissue samples or spoor) uncovered as of 2008. Local people, and later many around the world, have affectionately referred to the animal by the diminutive Nessie (Scottish Gaelic: "Niseag") since the 1950s.
The term "monster" was reportedly coined on 2 May 1933 by Alex Campbell, the water bailiff for Loch Ness and a part-time journalist, in a report in the Inverness Courier. On 4 August 1933, the Courier published as a full news item the claim of a London man named George Spicer that, a few weeks earlier, while motoring around the Loch, he and his wife had seen "the nearest approach to a dragon or pre-historic animal that I have ever seen in my life", trundling across the road toward the Loch carrying "an animal" in its mouth. The following month, another letter came from a veterinary student reporting a similar encounter while on a night drive. These stories soon reached the national press, and afterward the international, which talked of a 'monster fish', 'sea serpent' or 'dragon', eventually settling on 'Loch Ness Monster'. On 6 December 1933 the first photograph (taken by Hugh Gray) was published, and the creature received official recognition from the Secretary of State for Scotland, ordering the police to prevent any attacks on it. Other letters began appearing in the Courier, often anonymously, with claims of land or water sightings, either on the writer's part or on the parts of family, acquaintances or stories they remembered being told. In 1934, interest was further sparked by what is known as "The Surgeon's Photograph" (see above). In the same year R. T. Gould published a book, the first of many which describe the author's personal investigation and collected record of additional reports pre-dating the summer of 1933. Subsequent investigations by other agents over the ensuing decades added additional material which was eventually woven into a continuum of sightings dating from the 6th century A.D. to the present, which appeared to present a strong case for the existence of a large, possibly unknown and certainly unidentified animal or family of animals living in Loch Ness.
From 1933 onward, a picture has emerged from investigations of reports of large animals in the loch having existed for centuries, but in recent times have declined from over ten per year in the 1990s to three in 2006. Some believers have argued that a lengthy history of monster sightings in the loch provides ample evidence of the animal's existence in and of itself.