Stickmen (also called Stick figures) are stupid thin creatures created from stupid black lines. They do completely random and often stupid stuff, such as getting crushed by giant hamburgers (WHEAT DAAAAAAAAAAMN), pretending they're Darth Vader, play with guns, bombs & heroin, spray whipped cream all over the place and farting Shoop da Whoops. These things are very easy to kill, and enjoy killing each other and sometimes themselves.
They are EXTREMELY stupid, for the most part. Some are smart, but not many are.
Stick figures are often found in remote areas of Earth, but they have also been spotted on several other planets, most notably Mars. To find a stick figure, all you have to do is set off a bunch of fireworks. All nearby stick figures will start freaking out. You can also get out enough explosives and/or whipped cream. This generally draws out nearby stickmen.
Stickmen are considered a danger to themselves and society, and every country in the world (except for Soviet Russia) has a ban on them. The weird thing is, there aren't many stick figures in Russia. They all hide in other countries, just because they like breaking the rules. Stickmen are also tracked by the Men In Black, even though many of them aren't even aliens.
The average lifespan of a stick figure can change depending on certain conditions, but we understand they do not live very long, and since only they can get Fungi Fever this makes their lives even worse. They combat this by having millions of stickmen around the world. The first stickman sighting was in 2009, and it is believed they are a conspiracy by Google. This has not been confirmed, but we all know it's true.
In Teletubby Land, evil Stickmen with red eyes are just one species of evil creature that roam the land. On Alan Becker's series, "Animator Vs. Animation", there is a evil stick figure named The Chosen One which was accidentally brought to life by a chemical reaction in Flash 8.