Suicide (Latin suicidium, from sui caedere, to kill oneself) is the intentional taking of one's own life. Many dictionaries also note the metaphorical sense of "willful destruction of one's self-interest". Suicide may occur for a number of reasons, including depression, shame, guilt, desperation, physical pain, emotional pressure, anxiety, financial difficulties, or other undesirable situations. The World Health Organization noted that over one million people commit suicide every year, and that it is one of the leading causes of death among teenagers and adults under 35. There are an estimated 10 to 20 million non-fatal attempted suicides every year worldwide.

Views on suicide have been influenced by cultural views on existential themes such as religion, honor, and the meaning of life. The Abrahamic religions consider suicide an offense towards God due to religious belief in the sanctity of life. In the West it was often regarded as a serious crime. Japanese views on honor and religion led to seppuku, one of the most painful methods of suicide, to be respected as a means to atone for mistakes or failure, or as a form of protest during the samurai era. In the 20th century, suicide in the form of self-immolation has been used as a form of protest, and in the form of kamikaze and suicide bombing as a military or terrorist tactic. Sati is a Hindu funeral practice in which the widow would immolate herself on her husband's funeral pyre, either willingly, or under pressure from the family and in-laws.

Medically assisted suicide (euthanasia, or the right to die) is currently a controversial ethical issue involving people who are terminally ill, in extreme pain, and/or have minimal quality of life through injury or illness. Self-sacrifice for others is not usually considered suicide, as the goal is not to kill oneself but to save another.

The predominant view of modern medicine is that suicide is a mental health concern, associated with psychological factors such as the difficulty of coping with depression, inescapable suffering or fear, or other mental disorders and pressures. A suicide attempt is sometimes interpreted as a "cry for help" and attention, or to express despair and the wish to escape, rather than a genuine intent to die. Most people who attempt suicide do not complete suicide on a first attempt; those who later gain a history of repetitions have a significantly higher probability of eventual completion of suicide.

Epidemiology

main: Epidemiology of suicide According to official statistics, about a million people die by suicide annually, more than those murdered or killed in war. According to 2005 data, suicides in the U.S. outnumber homicides by nearly 2 to 1 and ranks as the 11th leading cause of death in the country, ahead of liver disease and Parkinson's disease. According to a 2008 report from the Johns Hopkins Bloomberg School of Public Health's, Center for Injury Research and Policy, the rate of suicide in the United States is increasing for the first time in a decade. The increase in the overall suicide rate between 1999 and 2005 was due primarily to an increase in suicides among whites aged 40–64, with white middle-aged women experiencing the largest annual increase. Worldwide suicide rates have increased by 60% in the past 50 years, mainly in the developing countries. Most suicides in the world occur in Asia, which is estimated to account for up to 60% of all suicides. According to the World Health Organization, China, India and Japan may account for 40% of all world suicides.