An orgasm is a sexual climax or peak. In a man, the feeling happens at the same time as he squirts semen out of his penis. In young boys, the feeling in the penis may happen, but there may be no semen. Semen release usually occurs only after puberty has started. Orgasm occurs as a result of continued sexual stimulation. During an orgasm, there is a strong feeling of excitement and intense physical pleasure. Sexual stimulation may be sexual intercourse, hand rubbing and squeezing, called masturbation, or other activities that excite the sex organs.

During an orgasm, a person's body usually spasms (shakes or trembles) and the person's brain activity changes quickly. A man's penis must get hard before he can have an orgasm. When a man has an orgasm he feels a very strong and incredibly enjoyable feeling, sometimes throughout his entire body. As he orgasms he has an ejaculation, which is when he releases semen through the tip of his penis without trying to. The hard penis becomes soft again after an orgasm. After orgasm, a male can experience a deep sense of relaxation, usually felt in the groin and the thighs. Usually the stronger the orgasm, the deeper the relaxation and the longer the relaxation will last.