Slenderman is an urban myth that consists of many known forms. Some say he has a human form with a suit and arms reaching down to his shins, others say he is treelike with tentacles that can reach at least 12 feet long. But to every form he has he is said to have no face.
The Slenderman has been said to date back to around 1400 TO 1500 A.D., where wives were supposed to have said that the tall man made them kill their husbands and children. The same goes with servants and maids murdering their masters. He has been seen all over the world, on all six continents, and there has been some talk of him being seen in Antarctica in the blizzards. In South America, they record how the Tree-Man takes victims, impales them on a tree, rips out their organs, puts them is bags, and sews them back in the body, and leaves them impaled on tree branches.
He is called many names in different cultures or beliefs. He has names like Slenderman, Slender-Man, Slender Man, the tall man, the thin man, the operator, the demon, fear dubh, and many more, but the most simple name is "Him". And also people call him Daddy
Even though the Slenderman’s origins start in the 1400s, there are also modern takes on the legend. His current day popularity took off due to a PhotoShop thread on the SomethingAwful forums in regards to urban legends, with two photos in regards to him appearing among children, along with a brief backup explanation on him. A very popular string of YouTube videos followed not long afterwards entitled Marble Hornets, which was originally going to be a student film set in a small town. However, its creator, Alex Kralie, stopped filming after a period of weeks due to "unworkable conditions" on the set. His friend, Jay (also known as J) later took possession of Kralie’s tapes, finding Slender Man in many shots, which he then started tormenting Jay in real life not long afterwards, as interaction with Slender Man resulted in mental problems, memory loss, electrical equipment problems and blackouts. In this version, Slender Man also has a possible henchman known as Totheark, although his association with Slender Man is not entirely clear. The series started in 2009, and by 2013 the videos have had over 62,000,000 views while in its third (and reportedly final) season, along with the first two seasons being released on DVD.
Due to the legend being public domain, there have been many take-offs of Slenderman, which also includes the CaughtnotSleeping, EverymanHYBRID, TribeTwelve, DarkHarvest00, and MLAndersen0 channels on YouTube, among many. And with his popularity growing, Slenderman has also become the subject of parodies, such as with Marble Bumblebee (spoofing Marble Hornets), Splendorman (he becomes totally harmless), and even in an animated form with Concrete Giraffes (along with speaking for the first time, plus we learn his first name is Jack [or at least in this version], although he still kills children).
And Slenderman’s modern legacy has also continued in two online games so far: Slender The Eight Pages and Slender The Arrival. In both games, you move around, trying to collect eight pages while trying to avoid the Slenderman, armed with only a flashlight.