A crop circle, crop formation, or corn circle is a pattern created by flattening a crop, usually a cereal. The term was first coined in the early 1980s by Colin Andrews. Crop circles have been described as all falling "within the range of the sort of thing done in hoaxes" by Taner Edis, professor of physics at Truman State University. Although obscure natural causes or alien origins of crop circles are suggested by fringe theorists, there is no scientific evidence for such explanations, and all crop circles are consistent with human causation.

Taner Edis is a Turkish American physicist and skeptic. He is a professor of physics at Truman State University. He received his B.S. from Boğaziçi University in Turkey and his M.A. and Ph.D. from Johns Hopkins University. Edis is the author of several books on creationism, religion and science. He is a scientific and technical consultant for the Committee for Skeptical Inquiry.