Human sexual activity, human sexual practice or human sexual behaviour is the manner in which
human
Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture ...
s experience and express their
sexuality. People engage in a variety of sexual acts, ranging from activities done alone (e.g.,
masturbation
Masturbation is the sexual stimulation of one's own genitals for sexual arousal or other sexual pleasure, usually to the point of orgasm. The stimulation may involve hands, fingers, everyday objects, sex toys such as vibrators, or combinatio ...
) to acts with another person (e.g.,
sexual intercourse
Sexual intercourse (or coitus or copulation) is a sexual activity typically involving the insertion and thrusting of the penis into the vagina for sexual pleasure or reproduction.Sexual intercourse most commonly means penile–vaginal penetr ...
,
non-penetrative sex
Non-penetrative sex or outercourse is sexual activity that usually does not include sexual penetration. It generally excludes the penetrative aspects of vaginal, anal, or oral sexual activity, but includes various forms of sexual and non-sexu ...
,
oral sex
Oral sex, sometimes referred to as oral intercourse, is sexual activity involving the stimulation of the genitalia of a person by another person using the mouth (including the lips, tongue, or teeth) and the throat. Cunnilingus is oral sex pe ...
, etc.)
in varying patterns of frequency, for a wide variety of reasons. Sexual activity usually results in
sexual arousal
Sexual arousal (also known as sexual excitement) describes the physiological and psychological responses in preparation for sexual intercourse or when exposed to sexual stimuli. A number of physiological responses occur in the body and mind ...
and physiological changes in the aroused person, some of which are pronounced while others are more subtle. Sexual activity may also include conduct and activities which are intended to arouse the sexual interest of another or enhance the
sex life of another, such as strategies to find or attract partners (
courtship
Courtship is the period wherein some couples get to know each other prior to a possible marriage. Courtship traditionally may begin after a betrothal and may conclude with the celebration of marriage. A courtship may be an informal and private ...
and
display behaviour), or personal interactions between individuals (for instance,
foreplay
Foreplay is a set of emotionally and physically intimate acts between one or more people meant to create sexual arousal and desire for sexual activity. Although foreplay is typically understood as physical sexual activity, nonphysical activiti ...
or
BDSM
BDSM is a variety of often erotic practices or roleplaying involving bondage, discipline, dominance and submission, sadomasochism, and other related interpersonal dynamics. Given the wide range of practices, some of which may be engaged in ...
). Sexual activity may follow sexual arousal.
Human sexual activity has sociological, cognitive,
emotional
Emotions are mental states brought on by neurophysiological changes, variously associated with thoughts, feelings, behavioral responses, and a degree of pleasure or displeasure. There is currently no scientific consensus on a definitio ...
,
behavioural
Behavior (American English) or behaviour (British English) is the range of actions and mannerisms made by individuals, organisms, systems or artificial entities in some environment. These systems can include other systems or organisms as we ...
and biological aspects; these include
personal bonding, sharing emotions and the
physiology
Physiology (; ) is the scientific study of functions and mechanisms in a living system. As a sub-discipline of biology, physiology focuses on how organisms, organ systems, individual organs, cells, and biomolecules carry out the chemi ...
of the
reproductive system
The reproductive system of an organism, also known as the genital system, is the biological system made up of all the anatomical organs involved in sexual reproduction. Many non-living substances such as fluids, hormones, and pheromones are als ...
,
sex drive, sexual intercourse and sexual behaviour in all its forms.
In some cultures, sexual activity is considered acceptable only within marriage, while
premarital and
extramarital sex
Extramarital sex occurs when a married person engages in sexual activity with someone other than their spouse.
The term may be applied to the situation of a single person having sex with a married person.
Where extramarital sexual relations do n ...
are
taboo
A taboo or tabu is a social group's ban, prohibition, or avoidance of something (usually an utterance or behavior) based on the group's sense that it is excessively repulsive, sacred, or allowed only for certain persons.''Encyclopædia Britannica ...
. Some sexual activities are illegal either universally or in some countries or subnational jurisdictions, while some are considered contrary to the
norm
Naturally occurring radioactive materials (NORM) and technologically enhanced naturally occurring radioactive materials (TENORM) consist of materials, usually industrial wastes or by-products enriched with radioactive elements found in the envir ...
s of certain societies or cultures. Two examples that are criminal offences in most
jurisdiction
Jurisdiction (from Latin 'law' + 'declaration') is the legal term for the legal authority granted to a legal entity to enact justice. In federations like the United States, areas of jurisdiction apply to local, state, and federal levels.
Jur ...
s are
sexual assault
Sexual assault is an act in which one intentionally sexually touches another person without that person's consent, or coerces or physically forces a person to engage in a sexual act against their will. It is a form of sexual violence, whic ...
and sexual activity with a person below the local
age of consent
The age of consent is the age at which a person is considered to be legally competent to consent to sexual acts. Consequently, an adult who engages in sexual activity with a person younger than the age of consent is unable to legally clai ...
.
Types
Sexual activity can be classified in a number of ways. The practices may be preceded by or consist solely of
foreplay
Foreplay is a set of emotionally and physically intimate acts between one or more people meant to create sexual arousal and desire for sexual activity. Although foreplay is typically understood as physical sexual activity, nonphysical activiti ...
.
Acts which involve one person (also called
autoeroticism) may include
sexual fantasy
A sexual fantasy or erotic fantasy is a mental image or pattern of thought that stirs a person's sexuality and can create or enhance sexual arousal. A sexual fantasy can be created by the person's imagination or memory, and may be triggered aut ...
or
masturbation
Masturbation is the sexual stimulation of one's own genitals for sexual arousal or other sexual pleasure, usually to the point of orgasm. The stimulation may involve hands, fingers, everyday objects, sex toys such as vibrators, or combinatio ...
.
If two or more people are involved, they may engage in
vaginal sex
Sexual intercourse (or coitus or copulation) is a sexual activity typically involving the insertion and thrusting of the penis into the vagina for sexual pleasure or reproduction.Sexual intercourse most commonly means penile–vaginal penetr ...
,
anal sex
Anal sex or anal intercourse is generally the insertion and thrusting of the erect penis into a person's anus, or anus and rectum, for sexual pleasure.Sepages 270–271for anal sex information, anpage 118for information about the clitoris. ...
,
oral sex
Oral sex, sometimes referred to as oral intercourse, is sexual activity involving the stimulation of the genitalia of a person by another person using the mouth (including the lips, tongue, or teeth) and the throat. Cunnilingus is oral sex pe ...
or
mutual masturbation
Non-penetrative sex or outercourse is sexual activity that usually does not include sexual penetration. It generally excludes the penetrative aspects of vaginal, anal, or oral sexual activity, but includes various forms of sexual and non-sex ...
.
Penetrative sex between two people may be described as
sexual intercourse
Sexual intercourse (or coitus or copulation) is a sexual activity typically involving the insertion and thrusting of the penis into the vagina for sexual pleasure or reproduction.Sexual intercourse most commonly means penile–vaginal penetr ...
, but definitions vary. If there are more than two participants in a sex act, it may be referred to as
group sex
Group sex is sexual behavior involving more than two participants. Participants in group sex can be of any sexual orientation or gender. Any form of sexual activity can be adopted to involve more than two participants, but some forms have thei ...
. Autoerotic sexual activity can involve use of
dildo
A dildo is a sex toy, often explicitly phallic in appearance, intended for sexual penetration or other sexual activity during masturbation or with sex partners. Dildos can be made from a number of materials and shaped like an erect human pe ...
s,
vibrators,
butt plug
A butt plug is a sex toy that is designed to be inserted into the rectum for sexual pleasure. They are similar to a dildo in some ways but tend to be shorter and have a flanged end to prevent the device from being lost inside the rectum.
Histor ...
s, and other
sex toy
A sex toy is an object or device that is primarily used to facilitate human sexual pleasure, such as a dildo, artificial vagina or vibrator. Many popular sex toys are designed to resemble human genitals, and may be vibrating or non-vibratin ...
s, though these devices can also be used with a partner.
Sexual activity can be classified into the
gender
Gender is the range of characteristics pertaining to femininity and masculinity and differentiating between them. Depending on the context, this may include sex-based social structures (i.e. gender roles) and gender identity. Most cultures us ...
and
sexual orientation
Sexual orientation is an enduring pattern of romantic or sexual attraction (or a combination of these) to persons of the opposite sex or gender, the same sex or gender, or to both sexes or more than one gender. These attractions are generally ...
of the participants, as well as by the relationship of the participants. The relationships can be ones of marriage,
intimate partner
An intimate relationship is an interpersonal relationship that involves physical or emotional intimacy. Although an intimate relationship is commonly a sexual relationship, it may also be a non-sexual relationship involving family, friends, o ...
s, casual
sex partners or
anonymous. Sexual activity can be regarded as
conventional or as
alternative, involving, for example,
fetishism
A fetish (derived from the French , which comes from the Portuguese , and this in turn from Latin , 'artificial' and , 'to make') is an object believed to have supernatural powers, or in particular, a human-made object that has power over oth ...
or
BDSM
BDSM is a variety of often erotic practices or roleplaying involving bondage, discipline, dominance and submission, sadomasochism, and other related interpersonal dynamics. Given the wide range of practices, some of which may be engaged in ...
activities.
Fetishism can take many forms, including the desire for certain body parts (
partialism) such as breasts, navels, or feet.
The object of desire can be shoes, boots, lingerie, clothing, leather or rubber items. Some non-conventional autoerotic practices can be dangerous. These include
erotic asphyxiation and
self-bondage
Self-bondage refers to the use of restraints on oneself for erotic pleasure. It is a form of erotic bondage which can be practiced alone.
Self-bondage is characterized by experimentation and ingenuity, and can be riskier than conventional bond ...
.
The potential for injury or even death that exists while engaging in the partnered versions of these fetishes (
choking and
bondage, respectively) becomes drastically increased in the autoerotic case due to the isolation and lack of assistance in the event of a problem.
Sexual activity that is consensual is sexual activity in which both or all participants agree to take part and are of the age that they can consent.
If sexual activity takes place under force or duress, it is considered rape or another form of
sexual assault
Sexual assault is an act in which one intentionally sexually touches another person without that person's consent, or coerces or physically forces a person to engage in a sexual act against their will. It is a form of sexual violence, whic ...
. In different cultures and countries, various sexual activities may be lawful or illegal in regards to the age, gender, marital status or other factors of the participants, or otherwise contrary to
social norms
Social norms are shared standards of acceptable behavior by groups. Social norms can both be informal understandings that govern the behavior of members of a society, as well as be codified into rules and laws. Social normative influences or soc ...
or generally accepted
sexual morals.
Mating strategies
In
evolutionary psychology
Evolutionary psychology is a theoretical approach in psychology that examines cognition and behavior from a modern evolutionary perspective. It seeks to identify human psychological adaptations with regards to the ancestral problems they evolv ...
and
behavioral ecology, human mating strategies are a set of behaviors used by individuals to attract, select, and retain
mates. Mating strategies overlap with
reproductive
The reproductive system of an organism, also known as the genital system, is the biological system made up of all the anatomical organs involved in sexual reproduction. Many non-living substances such as fluids, hormones, and pheromones are al ...
strategies, which encompass a broader set of behaviors involving the timing of reproduction and the trade-off between quantity and quality of offspring (see
life history theory).
Relative to other animals, human mating strategies are unique in their relationship with cultural variables such as the institution of
marriage
Marriage, also called matrimony or wedlock, is a culturally and often legally recognized union between people called spouses. It establishes rights and obligations between them, as well as between them and their children, and between t ...
. Humans may seek out individuals with the intention of forming a long-term
intimate relationship, marriage,
casual relationship, or
friendship
Friendship is a relationship of mutual affection between people. It is a stronger form of interpersonal bond than an "acquaintance" or an "association", such as a classmate, neighbor, coworker, or colleague.
In some cultures, the concept o ...
. The human desire for
companionship is one of the strongest human drives. It is an innate feature of human nature, and may be related to the
sex drive. The human mating process encompasses the social and cultural processes whereby one person may meet another to assess suitability, the
courtship
Courtship is the period wherein some couples get to know each other prior to a possible marriage. Courtship traditionally may begin after a betrothal and may conclude with the celebration of marriage. A courtship may be an informal and private ...
process and the process of forming an
interpersonal relationship
The concept of interpersonal relationship involves social associations, connections, or affiliations between two or more people. Interpersonal relationships vary in their degree of intimacy or self-disclosure, but also in their duration, in t ...
. Commonalities, however, can be found between humans and nonhuman animals in mating behavior.
Stages of physiological arousal during sexual stimulation

The
physiological responses during
sexual stimulation
Sexual stimulation is any stimulus (including bodily contact) that leads to, enhances and maintains sexual arousal, and may lead to orgasm. Although sexual arousal may arise without physical stimulation, achieving orgasm usually requires physica ...
are fairly similar for both men and women and there are four phases.
* During the excitement phase, muscle tension and blood flow increase in and around the sexual organs, heart and respiration increase and blood pressure rises. Men and women experience a "
sex flush" on the skin of the upper body and face. Typically, a woman's
vagina
In mammals, the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen ...
becomes lubricated and her
clitoris becomes swollen.
A man's
penis
A penis (plural ''penises'' or ''penes'' () is the primary sexual organ that male animals use to inseminate females (or hermaphrodites) during copulation. Such organs occur in many animals, both vertebrate and invertebrate, but males do ...
will become erect.
* During the plateau phase, heart rate and muscle tension increase further. A man's urinary bladder closes to prevent urine from mixing with
semen
Semen, also known as seminal fluid, is an organic bodily fluid created to contain spermatozoa. It is secreted by the gonads (sexual glands) and other sexual organs of male or hermaphroditic animals and can fertilize the female ovum. Sem ...
. A woman's clitoris may withdraw slightly and there is more lubrication, outer swelling and muscles tighten and reduction of diameter.
* During the
orgasm
Orgasm (from Greek , ; "excitement, swelling") or sexual climax is the sudden discharge of accumulated sexual excitement during the sexual response cycle, resulting in rhythmic, involuntary muscular contractions in the pelvic region chara ...
phase, breathing becomes extremely rapid and the pelvic muscles begin a series of rhythmic contractions. Both men and women experience quick cycles of muscle contraction of lower pelvic muscles and women often experience uterine and vaginal contractions; this experience can be described as intensely pleasurable, but roughly 15% of women never experience orgasm and half report having
faked it.
A large genetic component is associated with how often women experience orgasm.
* During the resolution phase, muscles relax, blood pressure drops, and the body returns to its resting state. Though generally reported that women do not experience a
refractory period and thus can experience an additional orgasm, or multiple orgasms soon after the first,
some sources state that both men and women experience a refractory period because women may also experience a period after orgasm in which further sexual stimulation does not produce excitement.
This period may last from minutes to days and is typically longer for men than women.
Sexual dysfunction
Sexual dysfunction is difficulty experienced by an individual or partners during any stage of normal sexual activity, including physical pleasure, desire, preference, arousal, or orgasm. The World Health Organization defines sexual dysfunction ...
is the inability to react emotionally or physically to sexual stimulation in a way projected of the average healthy person; it can affect different stages in the sexual response cycles, which are desire, excitement and orgasm. In the media, sexual dysfunction is often associated with men, but in actuality, it is more commonly observed in females (43 percent) than males (31 percent).
Psychological aspects
Sexual activity can lower blood pressure and overall stress levels.
It serves to release tension, elevate mood, and possibly create a profound sense of relaxation, especially in the postcoital period. From a biochemical perspective, sex causes the release of
oxytocin
Oxytocin (Oxt or OT) is a peptide hormone and neuropeptide normally produced in the hypothalamus and released by the posterior pituitary. It plays a role in social bonding, reproduction, childbirth, and the period after childbirth. Oxytocin ...
and endorphins and boosts the immune system.
Motivations
People engage in sexual activity for any of a multitude of possible reasons. Although the primary evolutionary purpose of sexual activity is reproduction, research on college students suggested that people have sex for four general reasons: ''physical attraction'', as a ''means to an end'', to increase ''emotional connection'', and to ''alleviate insecurity''.
Most people engage in sexual activity because of pleasure they derive from the
arousal of their sexuality, especially if they can achieve
orgasm
Orgasm (from Greek , ; "excitement, swelling") or sexual climax is the sudden discharge of accumulated sexual excitement during the sexual response cycle, resulting in rhythmic, involuntary muscular contractions in the pelvic region chara ...
. Sexual arousal can also be experienced from
foreplay
Foreplay is a set of emotionally and physically intimate acts between one or more people meant to create sexual arousal and desire for sexual activity. Although foreplay is typically understood as physical sexual activity, nonphysical activiti ...
and flirting, and from
fetish or BDSM activities, or other
erotic activities. Most commonly, people engage in sexual activity because of the
sexual desire
Sexual desire is an emotion and motivational state characterized by an interest in sexual objects or activities, or by a drive to seek out sexual objects or to engage in sexual activities. It is an aspect of sexuality, which varies significantly ...
generated by a person to whom they feel
sexual attraction; but they may engage in sexual activity for the physical satisfaction they achieve in the absence of attraction for another, as in the case of
casual or social sex. At times, a person may engage in a sexual activity solely for the sexual pleasure of their partner, such as because of an obligation they may have to the partner or because of love, sympathy or
pity
Pity is a sympathetic sorrow evoked by the suffering of others, and is used in a comparable sense to '' compassion'', '' condolence'' or ''empathy'' – the word deriving from the Latin '' pietas'' (etymon also of ''piety''). Self-pity is ...
they may feel for the partner.
A person may engage in sexual activity for purely monetary considerations, or to obtain some advantage from either the partner or the activity. A man and woman may engage in sexual intercourse with the objective of
conception. Some people engage in hate sex, which occurs between two people who strongly dislike or annoy each other. It is related to the idea that opposition between two people can heighten
sexual tension, attraction and interest.
Self-determination theory
Research has found that people also engage in sexual activity for reasons associated with
self-determination theory
Self-determination theory (SDT) is a macro theory of human motivation and personality that concerns people's innate growth tendencies and innate psychological needs. It pertains to the motivation behind people's choices in the absence of extern ...
. The self-determination theory can be applied to a sexual relationship when the participants have positive feelings associated with the relationship. These participants do not feel guilty or coerced into the partnership. Researchers have proposed the model of self-determined sexual motivation. The purpose of this model is to connect self-determination and sexual motivation.
This model has helped to explain how people are sexually motivated when involved in self-determined dating relationships. This model also links the positive outcomes, (satisfying the need for autonomy, competence, and relatedness) gained from sexual motivations.
According to the completed research associated with this model, it was found that people of both sexes who engaged in sexual activity for self-determined motivation had more positive psychological well-being.
While engaging in sexual activity for self-determined reasons, the participants also had a higher need for fulfillment. When this need was satisfied, they felt better about themselves. This was correlated with greater closeness to their partner and higher overall satisfaction in their relationship.
Though both sexes engaged in sexual activity for self-determined reasons, there were some differences found between males and females. It was concluded that females had more motivation than males to engage in sexual activity for self-determined reasons.
Females also had higher satisfaction and relationship quality than males did from the sexual activity.
Overall, research concluded that psychological well-being, sexual motivation, and sexual satisfaction were all positively correlated when dating couples partook in sexual activity for self-determined reasons.
Frequency
The frequency of sexual activity might range from zero to 15 or 20 times a week.
Frequency of intercourse tends to decline with age.
Some post-
menopausal women experience declines in frequency of sexual intercourse, while others do not.
According to the
Kinsey Institute
The Kinsey Institute for Research in Sex, Gender, and Reproduction (often shortened to The Kinsey Institute) is a research institute at Indiana University. Established in Bloomington, Indiana, in 1947 as a nonprofit, the institute merged with Indi ...
, the average frequency of sexual intercourse in the US for individuals who have partners is 112 times per year (age 18–29), 86 times per year (age 30–39), and 69 times per year (age 40–49).
Adolescents
The age at which adolescents tend to become sexually active varies considerably between different cultures and from time to time. (See
Prevalence of virginity.) The first sexual act of a child or adolescent is sometimes referred to as the
sexualization
Sexualization (or sexualisation) is to make something sexual in character or quality or to become aware of sexuality, especially in relation to men and women. Sexualization is linked to sexual objectification. According to the American Psycholog ...
of the child, and may be considered as a milestone or a change of status, as the loss of
virginity or innocence. Youth are legally free to have intercourse after they reach the
age of consent
The age of consent is the age at which a person is considered to be legally competent to consent to sexual acts. Consequently, an adult who engages in sexual activity with a person younger than the age of consent is unable to legally clai ...
.
A 1999 survey of students indicated that approximately 40% of ninth graders across the United States report having had sexual intercourse. This figure rises with each grade. Males are more sexually active than females at each of the grade levels surveyed. Sexual activity of young adolescents differs in ethnicity as well. A higher percent of African American and Hispanic adolescents are shown to be more sexually active than White adolescents.
Research on sexual frequency has also been conducted solely on female adolescents who engage in sexual activity. Female adolescents tended to engage in more sexual activity due to positive mood. In female teenagers, engaging in sexual activity was directly positively correlated with being older, greater sexual activity in the previous week or prior day, and more positive mood the previous day or the same day as the sexual activity occurred.
Decreased sexual activity was associated with prior or current day negative mood or menstruation.
Although opinions differ, others suggest that sexual activity is an essential part of humans, and that teenagers need to experience sex. According to a research study, sexual experiences help teenagers understand pleasure and satisfaction.
In relation to hedonic and eudaimonic well-being, it stated that teenagers can positively benefit from sexual activity. The cross-sectional study was conducted in 2008 and 2009 at a rural upstate New York community. Teenagers who had their first sexual experience at age 16 revealed a higher well-being than those who were sexually inexperienced or who were first sexually active at a later age of 17.
Furthermore, teenagers who had their first sexual experience at age 15 or younger, or who had many sexual partners were not negatively affected and did not have associated lower well-being.
Health and safety
Sexual activity is an innately physiological function, but like other physical activity, it comes with risks. There are four main types of risks that may arise from sexual activity:
unwanted pregnancy
Unintended pregnancies are pregnancies that are mistimed, unplanned or unwanted at the time of conception.
Sexual activity without the use of effective contraception through choice or coercion is the predominant cause of unintended pregnancy. Wo ...
, contracting a
sexually transmitted infection
Sexually transmitted infections (STIs), also referred to as sexually transmitted diseases (STDs) and the older term venereal diseases, are infections that are spread by sexual activity, especially vaginal intercourse, anal sex, and oral ...
(STI/STD), physical injury, and psychological injury.
Unwanted pregnancy
Any sexual activity that involves the introduction of semen into a woman's vagina, such as during sexual intercourse, or contact of semen with her vulva, may result in a pregnancy. To reduce the risk of unintended pregnancies, some people who engage in penile-vaginal sex may use
contraception
Birth control, also known as contraception, anticonception, and fertility control, is the use of methods or devices to prevent unwanted pregnancy. Birth control has been used since ancient times, but effective and safe methods of birth contr ...
, such as
birth control pill
The combined oral contraceptive pill (COCP), often referred to as the birth control pill or colloquially as "the pill", is a type of birth control that is designed to be taken orally by women. The pill contains two important hormones: progesti ...
s, a
condom
A condom is a sheath-shaped barrier device used during sexual intercourse to reduce the probability of pregnancy or a sexually transmitted infection (STI). There are both male and female condoms. With proper use—and use at every act of int ...
,
diaphragms,
spermicides,
hormonal contraception
Hormonal contraception refers to birth control methods that act on the endocrine system. Almost all methods are composed of steroid hormones, although in India one selective estrogen receptor modulator is marketed as a contraceptive. The origina ...
or sterilization.
The effectiveness of the various contraceptive methods in avoiding pregnancy varies considerably, and depends on the method rather than the user.
Sexually transmitted infections

Sexual activity that involves skin-to-skin contact, exposure to an infected person's
bodily fluids or
mucous membrane
A mucous membrane or mucosa is a membrane that lines various cavities in the body of an organism and covers the surface of internal organs. It consists of one or more layers of epithelial cells overlying a layer of loose connective tissue. It is ...
s carries the risk of contracting a sexually transmitted infection. People may not be able to detect that their
sexual partner has one or more STIs, for example if they are asymptomatic (show no symptoms).
[King, B. (2009). Human Sexuality Today (Sixth ed.). Upper Saddle River: Pearson Education, Inc.] The risk of STIs can be reduced by
safe sex
Safe sex is sexual activity using methods or contraceptive devices (such as condoms) to reduce the risk of transmitting or acquiring sexually transmitted infections (STIs), especially HIV. "Safe sex" is also sometimes referred to as safer s ...
practices, such as using condoms. Both partners may opt to be tested for STIs before engaging in sex.
The exchange of body fluids is not necessary to contract an infestation of crab lice. Crab lice typically are found attached to hair in the pubic area but sometimes are found on coarse hair elsewhere on the body (for example, eyebrows, eyelashes, beard, mustache, chest, armpits, etc.). Pubic lice infestations (pthiriasis) are spread through direct contact with someone who is infested with the louse.
Some STIs like
HIV/AIDS
Human immunodeficiency virus infection and acquired immunodeficiency syndrome (HIV/AIDS) is a spectrum of conditions caused by infection with the human immunodeficiency virus (HIV), a retrovirus. Following initial infection an individual m ...
can also be contracted by using
IV drug needles after their use by an infected person, as well as through childbirth or
breastfeeding
Breastfeeding, or nursing, is the process by which human breast milk is fed to a child. Breast milk may be from the breast, or may be expressed by hand or pumped and fed to the infant. The World Health Organization (WHO) recommends that brea ...
.
Aging
Factors such as biological and psychological factors, diseases, mental conditions, boredom with the relationship, and widowhood have been found to contribute to a decrease in sexual interest and activity in old age, but older age does not eliminate the ability to enjoy sexual activity.
Orientations and society
Heterosexuality

Heterosexuality is the romantic or sexual attraction to the opposite sex. Heterosexual practices are institutionally privileged in most countries.
In some countries, mostly those where religion has a strong influence on
social policy
Social policy is a plan or action of government or institutional agencies which aim to improve or reform society.
Some professionals and universities consider social policy a subset of public policy, while other practitioners characterize soc ...
, marriage laws serve the purpose of encouraging people to have sex only within marriage.
Sodomy laws have been used to discourage same-sex sexual practices, but they may also affect opposite-sex sexual practices. Laws also ban adults from committing
sexual abuse
Sexual abuse or sex abuse, also referred to as molestation, is abusive sexual behavior by one person upon another. It is often perpetrated using force or by taking advantage of another. Molestation often refers to an instance of sexual assa ...
, committing sexual acts with anyone under an
age of consent
The age of consent is the age at which a person is considered to be legally competent to consent to sexual acts. Consequently, an adult who engages in sexual activity with a person younger than the age of consent is unable to legally clai ...
, performing sexual activities in public, and engaging in sexual activities for money (prostitution). Though these laws cover both same-sex and opposite-sex sexual activities, they may differ in regard to punishment, and may be more frequently (or exclusively) enforced on those who engage in same-sex sexual activities.
Different-sex sexual practices may be
monogamous
Monogamy ( ) is a form of dyadic relationship in which an individual has only one partner during their lifetime. Alternately, only one partner at any one time ( serial monogamy) — as compared to the various forms of non-monogamy (e.g., pol ...
, serially monogamous, or
polyamorous, and, depending on the definition of sexual practice,
abstinent or
autoerotic (including
masturbation
Masturbation is the sexual stimulation of one's own genitals for sexual arousal or other sexual pleasure, usually to the point of orgasm. The stimulation may involve hands, fingers, everyday objects, sex toys such as vibrators, or combinatio ...
). Additionally, different religious and political movements have tried to influence or control changes in sexual practices including courting and marriage, though in most countries changes occur at a slow rate.
Homosexuality

Homosexuality is the romantic or sexual attraction to the same sex. People with a homosexual orientation can express their sexuality in a variety of ways, and may or may not express it in their behaviors.
Research indicates that many gay men and lesbians want, and succeed in having, committed and durable relationships. For example, survey data indicate that between 40% and 60% of gay men and between 45% and 80% of lesbians are currently involved in a romantic relationship.
[What is the nature of same-sex relationships?]
American Psychological Association, Retrieved 25 December 2014
It is possible for a person whose sexual identity is mainly heterosexual to engage in sexual acts with people of the same sex. Gay and lesbian people who pretend to be heterosexual are often referred to as being
closeted (hiding their sexuality in "the closet"). "Closet case" is a derogatory term used to refer to people who hide their sexuality. Making that orientation public can be called "
coming out of the closet" in the case of voluntary disclosure or "
outing
Outing is the act of disclosing an LGBT person's sexual orientation or gender identity without that person's consent. It is often done for political reasons, either to instrumentalize homophobia in order to discredit political opponents or to com ...
" in the case of disclosure by others against the subject's wishes (or without their knowledge). Among some communities (called "men on the DL" or "
down-low"), same-sex sexual behavior is sometimes viewed as solely for physical pleasure.
Men who have sex with men
Men who have sex with men (MSM) are male persons who engage in sexual activity with members of the same sex. The term was created in the 1990s by epidemiologists to study the spread of disease among all men who have sex with men, regardless of ...
, as well as
women who have sex with women, or men on the "down-low" may engage in sex acts with members of the same sex while continuing sexual and romantic relationships with the opposite sex.

People who engage exclusively in same-sex sexual practices may not identify themselves as gay or lesbian. In sex-segregated environments, individuals may seek relationships with others of their own gender (known as
situational homosexuality). In other cases, some people may experiment or explore their sexuality with same (or different) sex sexual activity before defining their
sexual identity
Sexual identity is how one thinks of oneself in terms of to whom one is romantically and/or sexually attracted.
''Sex ...
. Despite stereotypes and common misconceptions, there are no forms of sexual acts exclusive to same-sex sexual behavior that cannot also be found in opposite-sex sexual behavior, except those involving the meeting of the genitalia between same-sex partners –
tribadism (generally
vulva
The vulva (plural: vulvas or vulvae; derived from Latin for wrapper or covering) consists of the external female sex organs. The vulva includes the mons pubis (or mons veneris), labia majora, labia minora, clitoris, vestibular bulbs, vul ...
-to-vulva rubbing, commonly known by its "scissoring" position) and
frot
Frot or frotting ( slang for frottage; ) is a non-penetrative form of male-to-male sexual activity that usually involves direct penis-to-penis contact. The term was popularized by gay men activists who disparaged the practice of anal sex, but ...
(generally
penis
A penis (plural ''penises'' or ''penes'' () is the primary sexual organ that male animals use to inseminate females (or hermaphrodites) during copulation. Such organs occur in many animals, both vertebrate and invertebrate, but males do ...
-to-penis rubbing).
Bisexuality and pansexuality
People who have a romantic or sexual attraction to both sexes are referred to as bisexual.
People who have a distinct but not exclusive preference for one sex/gender over the other may also identify themselves as bisexual.
Like gay and lesbian individuals, bisexual people who pretend to be heterosexual are often referred to as being
closeted.
Pansexuality (also referred to as omnisexuality) may or may not be subsumed under bisexuality, with some sources stating that bisexuality encompasses sexual or romantic attraction to all
gender identities.
Pansexuality is characterized by the potential for
aesthetic
Aesthetics, or esthetics, is a branch of philosophy that deals with the nature of beauty and taste, as well as the philosophy of art (its own area of philosophy that comes out of aesthetics). It examines aesthetic values, often expressed thr ...
attraction,
romantic love
Romance or romantic love is a feeling of love for, or a strong attraction towards another person, and the courtship behaviors undertaken by an individual to express those overall feelings and resultant emotions.
The ''Wiley Blackwell Encycl ...
, or sexual desire towards people without regard for their gender identity or
biological sex. Some pansexuals suggest that they are
gender-blind; that gender and sex are insignificant or irrelevant in determining whether they will be sexually attracted to others. As defined in the ''
Oxford English Dictionary
The ''Oxford English Dictionary'' (''OED'') is the first and foundational historical dictionary of the English language, published by Oxford University Press (OUP). It traces the historical development of the English language, providing a co ...
,'' pansexuality "encompasses all kinds of sexuality; not limited or inhibited in sexual choice with regards to gender or practice".
Other social aspects
General attitudes
Alex Comfort
Alexander Comfort (10 February 1920 – 26 March 2000) was a British scientist and physician known best for his nonfiction sex manual, '' The Joy of Sex'' (1972). He was an author of both fiction and nonfiction, as well as a gerontologis ...
and others propose three potential social aspects of sexual intercourse in humans, which are not mutually exclusive: reproductive, relational, and recreational. The development of
the contraceptive pill and other highly effective forms of
contraception
Birth control, also known as contraception, anticonception, and fertility control, is the use of methods or devices to prevent unwanted pregnancy. Birth control has been used since ancient times, but effective and safe methods of birth contr ...
in the mid- and late 20th century has increased people's ability to segregate these three functions, which still overlap a great deal and in complex patterns. For example: A fertile couple may have intercourse while using contraception to experience sexual pleasure (recreational) and also as a means of emotional intimacy (relational), thus deepening their bonding, making their relationship more stable and more capable of sustaining children in the future (deferred reproductive). This same couple may emphasize different aspects of intercourse on different occasions, being playful during one episode of intercourse (recreational), experiencing deep emotional connection on another occasion (relational), and later, after discontinuing contraception, seeking to achieve pregnancy (reproductive, or more likely reproductive and relational).
Religious and ethical
Human sexual activity is generally influenced by social rules that are culturally specific and vary widely.
Sexual ethics, morals, and norms relate to issues including deception/honesty, legality,
fidelity and consent. Some activities, known as
sex crimes
Sex and the law deals with the regulation by law of human sexual activity. Sex laws vary from one place or jurisdiction to another, and have varied over time. Unlawful sexual acts are called sex crimes.
Some laws regarding sexual activity are ...
in some locations, are illegal in some jurisdictions, including those conducted between (or among) consenting and competent adults (examples include
sodomy law and adult-adult
incest
Incest ( ) is human sexual activity between family members or close relatives. This typically includes sexual activity between people in consanguinity (blood relations), and sometimes those related by affinity (marriage or stepfamily), adopt ...
).
Some people who are in a relationship but want to hide polygamous activity (possibly of opposite sexual orientation) from their partner, may solicit consensual sexual activity with others through personal contacts,
online chat rooms, or, advertising in select media.
Swinging involves singles or partners in a
committed relationship engaging in sexual activities with others as a
recreational or social activity.
The increasing popularity of swinging is regarded by some as arising from the upsurge in sexual activity during the
sexual revolution of the 1960s.
Some people engage in various sexual activities as a business transaction. When this involves having sex with, or performing certain actual sexual acts for another person in exchange for money or something of value, it is called prostitution. Other aspects of the
adult industry include
phone sex operators,
strip club
A strip club is a venue where strippers provide adult entertainment, predominantly in the form of striptease or other erotic or exotic dances. Strip clubs typically adopt a nightclub or bar style, and can also adopt a theatre or cabaret-style. ...
s, and pornography.
Gender roles and the expression of sexuality
Social
gender roles
A gender role, also known as a sex role, is a social role encompassing a range of behaviors and attitudes that are generally considered acceptable, appropriate, or desirable for a person based on that person's sex. Gender roles are usually cente ...
can influence sexual behavior as well as the reaction of individuals and communities to certain incidents; the
World Health Organization
The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level of ...
states that, "Sexual violence is also more likely to occur where beliefs in male sexual entitlement are strong, where gender roles are more rigid, and in countries experiencing high rates of other types of violence." Some societies, such as those where the concepts of
family honor and female
chastity
Chastity, also known as purity, is a virtue related to temperance. Someone who is ''chaste'' refrains either from sexual activity considered immoral or any sexual activity, according to their state of life. In some contexts, for example when m ...
are very strong, may practice violent control of female sexuality, through practices such as
honor killings and
female genital mutilation
Female genital mutilation (FGM), also known as female genital cutting, female genital mutilation/cutting (FGM/C) and female circumcision, is the ritual cutting or removal of some or all of the external female genitalia. The practice is found ...
.
The relation between
gender equality
Gender equality, also known as sexual equality or equality of the sexes, is the state of equal ease of access to resources and opportunities regardless of gender, including economic participation and decision-making; and the state of valuing d ...
and sexual expression is recognized, and promotion of equity between men and women is crucial for attaining
sexual and
reproductive health
Sexual and reproductive health (SRH) is a field of research, healthcare, and social activism that explores the health of an individual's reproductive system and sexual wellbeing during all stages of their life.
The term can also be further de ...
, as stated by the UN
International Conference on Population and Development Program of Action:
:"Human sexuality and gender relations are closely interrelated and together affect the ability of men and women to achieve and maintain sexual health and manage their reproductive lives. Equal relationships between men and women in matters of sexual relations and reproduction, including full respect for the physical integrity of the human body, require mutual respect and willingness to accept responsibility for the consequences of sexual behaviour. Responsible sexual behaviour, sensitivity and equity in gender relations, particularly when instilled during the formative years, enhance and promote respectful and harmonious partnerships between men and women."
BDSM

BDSM is a variety of
erotic practices or
roleplaying
Role-playing or roleplaying is the changing of one's behaviour to assume a role, either unconsciously to fill a social role, or consciously to act out an adopted role. While the ''Oxford English Dictionary'' offers a definition of role-playing a ...
involving
bondage,
dominance and submission
Dominance and submission (also called D/s) is a set of behaviors, customs, and rituals involving the submission of one person to another in an erotic episode or lifestyle. It is a subset of BDSM. This form of sexual contact and pleasure has be ...
,
sadomasochism, and other interpersonal dynamics.
Given the wide range of practices, some of which may be engaged in by people who do not consider themselves as practicing BDSM, inclusion in the BDSM community or subculture usually being dependent on
self-identification and shared experience.
BDSM communities generally welcome anyone with a non-normative streak who identifies with the community; this may include
cross-dressers, extreme
body modification enthusiasts,
animal players, latex or
rubber aficionados, and others.
B/D (bondage and discipline) is a part of BDSM. Bondage includes the restraint of the body or mind.
D/s means "Dominant and submissive". A Dominant is one who takes control of a person who wishes to surrender control and a submissive is one who surrenders control to a person who wishes to take control.
S/M (sadism and masochism) is the other part of BDSM. A sadist is an individual who takes pleasure in the pain or humiliation of others and a masochist is an individual who takes pleasure from their own pain or humiliation.
Unlike the usual "power neutral" relationships and play styles commonly followed by couples, activities and relationships within a BDSM context are often characterized by the participants' taking on complementary, but unequal roles; thus, the idea of
informed consent
Informed consent is a principle in medical ethics and medical law, that a patient must have sufficient information and understanding before making decisions about their medical care. Pertinent information may include risks and benefits of treatm ...
of both the partners becomes essential. Participants who exert dominance (sexual or otherwise) over their partners are known as Dominants or
Tops
Total Operations Processing System (TOPS) is a computer system for managing railway locomotives and rolling stock, known for many years of use in the United Kingdom.
TOPS was originally developed between the Southern Pacific Railroad (SP), S ...
, while participants who take the passive, receiving, or obedient role are known as submissives or
bottoms.
These terms are sometimes shortened so that a dominant person may be referred to as a "Dom" (a woman may choose to use the feminine "Domme") and a submissive may be referred to as a "sub". Individuals who can change between Top/Dominant and bottom/submissive roles – whether from relationship to relationship or within a given relationship – are known as ''switches''. The precise definition of roles and self-identification is a common subject of debate within the community.
In a 2013 study, researchers stated that BDSM is a sexual act where participants play role games, use restraint, use power exchange,
use suppression and pain is sometimes involved depending on individual(s).
The study serves to challenge the widespread notion that BDSM could be in some way linked to
psychopathology
Psychopathology is the study of abnormal cognition, behaviour, and experiences which differs according to social norms and rests upon a number of constructs that are deemed to be the social norm at any particular era.
Biological psychopathol ...
. According to the findings, one who participates in BDSM may have greater strength socially and mentally as well as greater independence than those who do not practice BDSM.
It suggests that people who participate in BDSM play have higher subjective well-being, and that this might be due to the fact that BDSM play requires extensive communication. Before any act occurs, the partners must discuss their agreement of their relationship. They discuss how long the play will last, the intensity, their actions, what each participant needs or desires, and what, if any, sexual activities may be included. All acts must be consensual and pleasurable to both parties.
In a 2015 study, interviewed BDSM participants have mentioned that the activities have helped to create higher levels of connection, intimacy, trust and communication between partners.
The study suggests that Dominants and submissives exchange control for each other's pleasure and to satisfy a need. The participants have remarked that they enjoy pleasing their partner in any way they can and many surveyed have felt that this is one of the best things about BDSM. It gives a submissive pleasure to do things in general for their Dominant while a Dominant enjoys making their encounters all about their submissive and enjoy doing things that makes their submissive happy. The findings indicate that the surveyed submissives and Dominants found BDSM makes play more pleasurable and fun. The participants have also mentioned improvements in their personal growth, romantic relationships, sense of community and self, the dominant's confidence, and their coping with everyday things by giving them a psychological release.
Legal issues
There are many laws and social customs which prohibit, or in some way affect sexual activities. These laws and customs vary from country to country, and have varied over time. They cover, for example, a prohibition to non-consensual sex, to sex outside marriage, to sexual activity in public, besides many others. Many of these restrictions are non-controversial, but some have been the subject of public debate.
Most societies consider it a serious crime to force someone to engage in sexual acts or to engage in sexual activity with someone who does not consent. This is called
sexual assault
Sexual assault is an act in which one intentionally sexually touches another person without that person's consent, or coerces or physically forces a person to engage in a sexual act against their will. It is a form of sexual violence, whic ...
, and if sexual penetration occurs it is called rape, the most serious kind of sexual assault. The details of this distinction may vary among different legal jurisdictions. Also, what constitutes effective consent in sexual matters varies from culture to culture and is frequently debated. Laws regulating the minimum age at which a person can consent to have sex (
age of consent
The age of consent is the age at which a person is considered to be legally competent to consent to sexual acts. Consequently, an adult who engages in sexual activity with a person younger than the age of consent is unable to legally clai ...
) are frequently the subject of debate, as is
adolescent sexual behavior in general. Some societies have forced marriage, where consent may not be required.
Same-sex laws
Many locales have laws that limit or prohibit
same-sex sexual activity.
Sex outside marriage
In the West,
sex before marriage is not illegal. There are social taboos and many religions condemn pre-marital sex. In many Muslim countries, such as Saudi Arabia, Pakistan, Afghanistan,
Iran,
Kuwait, Maldives, Morocco, Oman, Mauritania, United Arab Emirates, Sudan, Yemen, any form of sexual activity outside marriage is illegal. Those found guilty, especially women, may be forced to wed the sexual partner, publicly beaten, or stoned to death. In many African and native tribes, sexual activity is not viewed as a privilege or right of a married couple, but rather as the unification of bodies and is thus not frowned upon.
Other studies have analyzed the changing attitudes about sex that American adolescents have outside marriage. Adolescents were asked how they felt about oral and vaginal sex in relation to their health, social, and emotional well-being. Overall, teenagers felt that oral sex was viewed as more socially positive amongst their demographic.
Results stated that teenagers believed that oral sex for dating and non-dating adolescents was less threatening to their overall values and beliefs than vaginal sex was.
When asked, teenagers who participated in the research viewed oral sex as more acceptable to their peers, and their personal values than vaginal sex.
Minimum age of sexual activity (age of consent)
The laws of each jurisdiction set the minimum age at which a young person is allowed to engage in sexual activity.
This
age of consent
The age of consent is the age at which a person is considered to be legally competent to consent to sexual acts. Consequently, an adult who engages in sexual activity with a person younger than the age of consent is unable to legally clai ...
is typically between 14 and 18 years, but laws vary. In many jurisdictions, age of consent is a person's mental or functional age.
As a result, those above the set age of consent may still be considered unable to legally consent due to mental immaturity.
Many jurisdictions regard any sexual activity by an adult involving a child as
child sexual abuse.
Age of consent may vary by the type of sexual act, the sex of the actors, or other restrictions such as abuse of a
position of trust. Some jurisdictions also make allowances for young people engaged in sexual acts with each other.
Incestuous relationships
Most jurisdictions prohibit sexual activity between certain close relatives. These laws vary to some extent; such acts are called
incest
Incest ( ) is human sexual activity between family members or close relatives. This typically includes sexual activity between people in consanguinity (blood relations), and sometimes those related by affinity (marriage or stepfamily), adopt ...
uous.
Incest laws may involve restrictions on
marriage
Marriage, also called matrimony or wedlock, is a culturally and often legally recognized union between people called spouses. It establishes rights and obligations between them, as well as between them and their children, and between t ...
rights, which also vary between jurisdictions. When incest involves an adult and a child, it is considered to be a form of
child sexual abuse.
Sexual abuse
Non-consensual sexual activity or subjecting an unwilling person to witnessing a sexual activity are forms of
sexual abuse
Sexual abuse or sex abuse, also referred to as molestation, is abusive sexual behavior by one person upon another. It is often perpetrated using force or by taking advantage of another. Molestation often refers to an instance of sexual assa ...
, as well as (in many countries) certain non-consensual paraphilias such as
frotteurism,
telephone scatophilia (indecent phonecalls), and non-consensual
exhibitionism
Exhibitionism is the act of exposing in a public or semi-public context one's intimate parts – for example, the breasts, genitals or buttocks. The practice may arise from a desire or compulsion to expose themselves in such a manner to group ...
and
voyeurism
Voyeurism is the sexual interest in or practice of watching other people engaged in intimate behaviors, such as undressing, sexual activity, or other actions of a private nature.
The term comes from the French ''voir'' which means "to see". ...
(known as "
indecent exposure" and "
peeping tom
Lady Godiva (; died between 1066 and 1086), in Old English , was a late Anglo-Saxon noblewoman who is relatively well documented as the wife of Leofric, Earl of Mercia, and a patron of various churches and monasteries. Today, she is mainly rem ...
" respectively).
Prostitution and survival sex
People sometimes exchange sex for money or access to other resources. Work takes place under many varied circumstances. The person who receives payment for sexual services is known as a prostitute and the person who receives such services is referred to by a multitude of terms, such as being a
client. Prostitution is one of the branches of the
sex industry
The sex industry (also called the sex trade) consists of businesses that either directly or indirectly provide sex-related products and services or adult entertainment. The industry includes activities involving direct provision of sex-related ...
. The
legal status of prostitution varies from
country to country, from being a punishable crime to a regulated profession. Estimates place the annual revenue generated from the global prostitution industry to be over $100 billion. Prostitution is sometimes referred to as "the world's oldest profession". Prostitution may be a voluntary individual activity or facilitated or
forced by
pimp
Procuring or pandering is the facilitation or provision of a prostitute or other sex worker in the arrangement of a sex act with a customer. A procurer, colloquially called a pimp (if male) or a madam (if female, though the term pimp has still ...
s.
Survival sex
Survival sex is a form of prostitution engaged in by a person because of their extreme need. It describes the practice of people who are homeless or otherwise disadvantaged in society, trading sex for food, a place to sleep, or other basic nee ...
is a form of prostitution engaged in by people in need, usually when
homeless
Homelessness or houselessness – also known as a state of being unhoused or unsheltered – is the condition of lacking stable, safe, and adequate housing. People can be categorized as homeless if they are:
* living on the streets, also kn ...
or otherwise disadvantaged people trade sex for food, a place to sleep, or other
basic needs
The basic needs approach is one of the major approaches to the measurement of absolute poverty in developing countries globally. It works to define the absolute minimum resources necessary for long-term physical well-being, usually in terms of c ...
, or for
drugs
A drug is any chemical substance that causes a change in an organism's physiology or psychology when consumed. Drugs are typically distinguished from food and substances that provide nutritional support. Consumption of drugs can be via inhalati ...
. The term is used by
sex trade and poverty researchers and
aid workers.
See also
*
Child sexuality
Development of sexuality is an integral part of the development and maturation of children. It includes a range of sensory, emotional, and consequent sexual activities that may occur before or during early puberty, but before full sexual maturity ...
*
Erotic plasticity
*
History of human sexuality
*
Human female sexuality
*
Human male sexuality
Human male sexuality encompasses a wide variety of feelings and behaviors. Men's feelings of attraction may be caused by various physical and social traits of their potential partner. Men's sexual behavior can be affected by many factors, incl ...
*
Mechanics of human sexuality
*
Orgasm control
*
Orgastic potency
Within the work of the Austrian psychoanalyst Wilhelm Reich (1897–1957), orgastic potency is a human's natural ability to experience an orgasm with certain psychosomatic characteristics
. "Reich's model takes a unisex, 'integrated biopsychologi ...
*
Sexual activity during pregnancy
*
Sociosexual orientation
*
Transgender sexuality
References
Further reading
Durex Global Sex Survey 2005(PDF) a
data360.org* Ryan, Christopher & Jetha, Cacilda, (2010).
''Sex at Dawn: The Prehistoric Origins of Modern Sexuality.'' New York: Harper.
{{DEFAULTSORT:Human Sexual Activity
Human sexual activity
Intimate relationships
Evolutionary psychology