Depending on the jurisdiction, prostitution law may deem commercial sex to be legal or illegal.

A person who works in this field is called a prostitute, and is a type of sex worker.

There are about 42 million prostitutes in the world, living all over the world (though most of Central Asia, the Middle East and Africa lacks data, studied countries in that large region rank as top sex tourism destinations).

Another explanation is that prostituta is a composition of pro and statuere (to cause to stand, to station, place erect).

In some places, men who drive around red-light districts for the purpose of soliciting prostitutes are also known as kerb crawlers. The prostitution metaphor, "traditionally used to signify political inconstancy, unreliability, fickleness, a lack of firm values and integrity, and venality, has long been a staple of Russian political rhetoric." In 1938, he used the same description for the Comintern, saying that the chief aim of the Bonapartist clique of Stalin during the preceding several years "has consisted in proving to the imperialist 'democracies' its wise conservatism and love for order.

The word "prostitution" can also be used metaphorically to mean debasing oneself or working towards an unworthy cause or "selling out". For the sake of the longed alliance with imperialist democracies [Stalin] has brought the Comintern to the last stages of political prostitution." Besides targeting political figures, the term is used in relation to organizations and even small countries, which "have no choice but to sell themselves", because their voice in world affairs is insignificant.

Those offering services to female customers are commonly known as gigolos; those offering services to male customers are hustlers or rent boys.

Clients of prostitutes are sometimes known as johns or tricks in North America and punters in the British Isles.

Most sex worker activists groups reject the word prostitute and since the late 1970s have used the term sex worker instead.

However, sex worker can also mean anyone who works within the sex industry or whose work is of a sexual nature and is not limited solely to prostitutes.

Trump was "prostituting himself to feed his ego and gain power" when he ran for President of the United States.

Sex work researcher and writer Gail Pheterson writes that these metaphorical usages exist because "the term "prostitute" gradually took on a Christian moralist tradition, as being synonymous with debasement of oneself or of others for the purpose of ill-gotten gains".

Prostitution is one branch of the sex industry, along with pornography, stripping, and erotic dancing.