An expression used to describe the act of hurting oneself, most of the time by cutting but also burning, breaking bones, hitting yourself etc.
It is a general view that people self harm for attention which is normally not the case. People who self harm are generally depressed and has a hard time dealing with life. Self harm also mustn't be mixed up with suicide, as it's not done for dying, but for coping with life.
Most people who self harm are ashamed and hide it, but there are those who aren't afraid to go in long sleeves (if they cut their arms) This is most of the time NOT because they want everyone to feel sorry for them.
Also smoking can technically be counted as self harm, as it's a way of hurting oneself, although not as direct as other ways.
"I hurt myself today, to see if I still feel, I focus on the pain, the only thing that's real. The needle tears a hole, the old familiar sting, tried to kill it all away but I remember everything." - Hurt, Nine Inch Nails