Sex work is "the exchange of sexual services, performances, or products for material compensation. It includes activities of direct physical contact between buyers and sellers as well as indirect sexual stimulation". Sex work only refers to voluntary sexual transactions; thus the term does not refer to human trafficking and other coerced or nonconsensual sexual transactions such as child prostitution. The transaction must take place between consenting adults who are of the legal age and mental capacity to consent and must take place without any methods of coercion. The term emphasizes the labor and economic implications of this type of work. Furthermore, some prefer the use of the term because it seemingly grants more agency to the sellers of these services.
Read article on Wikipedia