The Bogeyman (also spelled "Boogeyman", "Bogieman", and/or "Boogieman") is the archetype of the creature type known as Bogeymen (also spelled "Bogiemen", "Boogeymen", and/or "Boogiemen") - a monster that is designed as a tool to scare children into good behavior or to protect them from harm: the Bogeyman himself is a formless being that can take any shape the storyteller wishes though he tends to be a grotesque humanoid with a tendency to hide under beds, in closets and other dark places.
The Bogeyman is said to only go after naughty children and his punishments are said to vary from mischievous pranks such as pulling hair, biting toes or shaking beds (akin to a poltergeist) or more malevolent behavior such as manifesting as horrible creatures to scare the child or even going as far as kidnapping the child and taking them away to his shadowy realm to an undisclosed fate (though he is often said to eat them).
The Bogeyman is related to many similar beings - who, together, form an entire villain type in themselves: however he is definitely the most infamous of them all and is especially prominent in Western cultures. Even to this day, some people will use the Bogeyman to scare children into good behavior, though it is becoming less popular due to negative effects it can bring to some children - fear of the Bogeyman is also a natural part of children's development and it is very common for children to go through a period of fear over the Bogeyman in the closet or under their bed: usually people grow out of this fear when they grew older but the few who don't can suffer the curse of the Bogeyman for their entire lives (unless they are fortunate enough to get help in conquering this fear—Like the boy In the film "Boogeyman").
Some other villains have been mistaken for the Bogeyman, like Michael Myers or IT.
The Bogeyman has also been a legend since around 350 AD.
Boy Disappeared in the Closet
This true story was seen in an episode of Beyond Belief, Fact or Fiction. There was a child who told his mother that there was a formless monster living in his closet. She did not believe him. Some days later a child went inside the closet. The mother opened the closet door and found no one there. The police did not know what to think. The monster has never returned.
However, the story turned out to be false, as a new finding revealed that the boy secretly climbed out of the closet through a ceiling panel and went to a friend’s house. He hid there for some time, until the friend's mother found him in hiding in the attic.