Etymology
The word masturbation is believed by many to derive from the Greek word mezea (?????, "penises") and the Latin turbare ("to disturb"). A competing etymology based on the Latin manu stuprare ("to defile with the hand") is said by the Oxford English Dictionary to be an "old conjecture". The esoteric and little-used synonym manustupration is similarly derived from manus stuprare.

Masturbation techniques
Ways of masturbating common to members of both sexes include pressing or rubbing the genital area, either with the fingers or against an object such as a pillow; inserting fingers or an object into the anus (see anal masturbation); and stimulating the penis or vulva/clitoris with electric vibrators, which may also be inserted into the vagina or anus. Members of both sexes may also enjoy touching, rubbing, or pinching the nipples while masturbating. Both sexes sometimes use lubricating substances to intensify sensation.

Reading or viewing pornography, or sexual fantasy, are common adjuncts to masturbation in adolescence and adulthood. Masturbation activities are often ritualised. Various fetishes and paraphilias can also play a part in the masturbation ritual; potentially harmful or fatal activities include autoerotic asphyxiation and self-bondage.

Female
 Female masturbation techniques are numerous and perhaps more varied than those of males. They are influenced by a number of factors and personal preferences. Techniques include stroking or rubbing of the vulva, especially the clitoris, with the middle, index and/or second fingers. Sometimes one or more fingers may be inserted into the vagina to repeatedly stroke the frontal wall of the vagina where the g-spot is located. Masturbation aids such as a vibrator, dildo or Ben Wa balls can also be used to stimulate the vagina and clitoris. Many women will caress the breasts or stimulate a nipple with the free hand. Anal stimulation is also enjoyed by some because of the thousands of sensitive nerves located there.

Lubrication is sometimes used during masturbation, especially when penetration is involved, but this is by no means universal and many women find their natural lubrication sufficient—some even produce more lubricant alone than with a partner, though the reasons for this seem to be primarily psychological.

Women may masturbate in the bathtub, shower and hot tub, sometimes including the use of warm running water to stimulate the clitoris. Lying face down, one may straddle a pillow, the corner or edge of the bed, a partner's leg or some scrunched-up clothing and 'hump' the vulva and clitoris against it. Standing up, the corner of an item of furniture, or even a washing machine, can be used to stimulate the clitoris through the labia and clothing.

Some reach orgasm merely by crossing their legs tightly and clenching the muscles in their legs, which creates pressure on the genitals. This can potentially be done in public without observers noticing. Some prefer to use only pressure, applied to the clitoris without direct contact, for example by pressing the palm or ball of the hand against underwear or other clothing.

Very few women can orgasm spontaneously, after experiencing prior sexual arousal, due to intellectual stimulation alone, for instance listening to certain pieces of music. Often, these mental triggers have associations with previous instances of arousal and orgasm. Some women claim to be able to orgasm spontaneously by force of will alone, but that ability, if it exists at all, may not strictly qualify as masturbation as no physical stimulus is involved.

Those who have difficulty reaching orgasm through sexual intercourse may find it easier to achieve an orgasm through masturbation. Sometimes sex therapists will recommend that female patients take time to masturbate to orgasm, especially if they have not masturbated before.
 
 

Male
Male masturbation techniques are also influenced by a number of factors and personal preferences. Techniques may also differ between circumcised and uncircumcised males, as some techniques which may work for one can often be quite painful for the other.

The most common technique is to simply hold the penis with a loose fist and then to move the hand up and down the shaft until orgasm is achieved. When uncircumcised, stimulation of the penis comes from the pumping of the foreskin up and down the length of the shaft, which usually uncovers and covers the head in the process. This gliding motion of the foreskin reduces friction. When circumcised, on the other hand, the stimulation is sometimes from direct contact with the hand. Many massage (with some using a personal lubricant to reduce friction) the glans, the rim thereof and the notched indent left over from the removal of the frenulum.

Another technique is to place the index finger and thumb around the penis about halfway along the shaft and move the skin up and down to produce a pleasurable sensation. Another variation is to place fingers and thumbs on the penis as if playing a flute, and then shuttle them back and forth.

A less common technique is to lie face down on a comfortable surface such as a mattress or pillow and rub the penis against it until orgasm is achieved. Some people claim such masturbation may result in pain, irritation, or abrasion if performed too roughly. Other techniques include the use of an artificial vagina or simulacrum for masturbation. Many fondle their testicles, nipples or other parts of their body with the other hand while masturbating. Some may use vibrators and other sexual devices more commonly associated with female masturbation.

The prostate gland is one of the organs that contributes fluid to semen. As the prostate is touch-sensitive, some directly stimulate it using a well-lubricated finger or dildo inserted through the anus into the rectum. Stimulating the prostate from outside, via pressure on the perineum, can be pleasurable as well.

Ejaculation of semen is sometimes controlled by wearing a condom or by ejaculating onto a tissue or other item. A controversial ejaculation control technique is to put pressure on the perineum, about half way between the scrotum and the anus, just before ejaculating. This can, however, redirect semen into the bladder and the technique may cause long term damage due to the pressure put on the nerves and blood vessels in the perineum. A dry orgasm is one that is reached by withholding ejaculation. Proponents of tantric sex say that this is a learnable skill that can shorten the refractory period. Drugs, such as prolactin inhibitors, may also shorten the refractory period for a male. An example of this is the prescription drug Dostinex.

Males who can reach and stimulate their penis with their tongue or lips are said to be capable of autofellatio. Some men may taste or swallow their semen.

Historically, some have seen a connection between circumcision and masturbation frequency, which remains a debated topic. In a 1410-man survey in the United States in 1992, Laumann found that: "A total of 47% of circumcised men reported masturbating at least once a month vs 34% for their uncircumcised peers."

Health and psychological effects
It is held in many mental health circles that masturbation can relieve depression and lead to a higher sense of self-worth. Masturbation can also be particularly useful in relationships where one partner wants more sex than the other — in which case masturbation provides a balancing effect and thus a more harmonious relationship.

Both from the standpoint of avoiding unwanted pregnancy and that of avoiding sexually transmitted diseases, masturbation is the safest of sexual practices. There is no credible scientific or medical evidence that manual masturbation is damaging to either one's mental or physical health.

Law
In most countries, masturbation tends to be legal, even by children, as long as nobody else is involved and no image is made. However, a few jurisdictions in the U.S. do have laws against the distribution of masturbatory aids. These laws are largely not enforced.

Masturbation in a public place, and in cases where somebody else is unexpectedly confronted with it, is usually considered "lewd and lascivious" or "dissolute" behaviour, or at least indecent exposure, both of which are misdemeanors. According to some historic chronicles, it has not always been so.

Laws may vary for masturbation as part of a performance, as a visitor of a live or screen performance, as a participant in a sex party, etc.