The Sandman is a mythical being from folklore who is said to be the embodiment of dreams and rules over the realm of dreams and nightmares. Originating from Northern European lore, he brings good dreams by sprinkling magical sand onto the eyes of children while they sleep at night. The rheum in one's eyes upon waking is believed to be the result of the Sandman's work the previous evening.
There is also another creature bearing the name "Sandman", but this creature is very different. Its skin is that of a dead persons, decayed and discolored. It has very long fingers and many sharp teeth. It hides just out of sight in the dark and whispers "tik toc, tik toc" to its unlucky victim. This strange chant quickly puts the victim into a deep sleep.
Once asleep, the Sandman will come out of hiding and devour the sleeping victim with its sharp teeth. It only needs to feast once per night, but it will sometimes chose to kill for fun. This creature can only come out in the dark. It is said to be the evil brother of the good sandman, but some people disagree. This other Sandman could possibly be the Boogeyman.