Stabbing
A stabbing is penetration with a sharp or pointed object at close range. Stab connotes purposeful action, as by an assassin or murderer, but it is also possible to accidentally stab oneself or others. Stabbing differs from slashing or cutting in that the motion of the object used in a stabbing generally moves perpendicular to and directly into the victim's body, rather than being drawn across it.
Stabbings today are common among gangs and in prisons because knives are cheap, easy to acquire (or manufacture), easily concealable and relatively effective.
History
Stabbings have been common throughout human history and were the means used to assassinate a number of distinguished historical figures, such as Roman emperors Julius Caesar and Caligula.
In Japan, the historical practice of stabbing oneself deliberately in ritual suicide is known as seppuku (more colloquially hara-kiri, literally "belly-cutting" since it involves cutting open the abdomen). The ritual is highly codified, and the person committing suicide is assisted by a "second" who is entrusted to decapitate him cleanly (and thus expedite death and prevent an undignified spectacle) once he has made the abdominal wound.