Shadow people are an alleged supernatural phenomenon involving the manifestation of anthropomorphic shadow entities. They are also known as shadow folk, shadow beings, shadow men, or shades. According to witnesses, they are usually seen only in the corner of one's eye, only to disappear when an attempt is made to look at them directly. There is the claim that shadow people can move through walls. Two common types, according to paranormal enthusiasts, are the "hat man," a shadow person wearing a hat, and the "hooded man," a shade wearing a hood.
Sightings of shadow people usually report them as being near the fringes of a room (where shadows are common), and rarely, standing in doorways or in more prominent positions. They are most often seen indoors at night, though there are outdoor and daytime sightings. The shadow people generally only appear for a moment, quickly departing if closely examined. They have no discernible facial features. The distinction between a ghost and a shadow person is blurry. Generally a ghost is more of a light-colored apparition, while a shadow is dark.
Though some have claimed that shadow people are a component of old Native American belief, the phenomenon seems to be entirely modern, with them rarely being mentioned prior to 1990. In the early 2000s, a wave of interest into the phenomenon led to their introduction to modern culture. People have posted alleged videos of them on the Internet, but none are very convincing, a similarity these share with ghost videos. Paranormal enthusiasts attribute the origin to that similar to ghosts — psychic beings created after an event of great distress or a death. Another proposal is that shadow people are beings traveling from another dimension.
As with ghosts, most scientists are extremely skeptical about the existence of shadow people. It seems as if the phenomenon can be attributed to a mix of pareidolia (the tendency to see patterns everywhere) and the low-resolution nature of peripheral vision. Hypnagogia, the unusual mental state between waking and sleep, is also known to produce hallucinations of person-like entities, accompanied by feelings of unease and lack of control. Many skeptics assert that hypnagogia is likely responsible for most reports of alien abduction, so shadow people would just be another phenomena attributed to that hallucinatory state. Until a convincing video of shadow people is produced, it seems unlikely that the effect will be taken as anything genuinely supernatural by most of the population.