There have always been different types or classes of prostitutes. In ancient China, for example, one could distinguish between palace prostitutes, military prostitutes, indoor prostitutes, and market prostitutes. Depending on the degree of official tolerance during certain historical periods, one could also distinguish between legal and illegal prostitutes. In ancient Greece, where prostitution was legal, one recognized two major types - the ordinary prostitute (porne) and the high-class courtisan (hetaira). The ancient Romans knew many different categories, ranging from the accommodating serving girls in taverns (copae), outdoor prostitutes (lupae) and nightwalkers (noctiliae) to the kept women of the rich (delicatae). In addition, imperial China as well as ancient Greece and Rome had regulated brothels.
In our modern world, we also find a great number of different forms of prostitution, and the present electronic revolution is creating new ones. However, the practical details vary a great deal from country to country, because they are shaped by many socio-cultural factors. These include the various criminal and civil laws and their interpretation and enforcement, religious traditions, the general status of women, the level of poverty, the type and extent of tourism, the degree of technological development, and many more. The present course, therefore, cannot provide a complete or even adequate description of all now existing forms of prostitution. Instead, we will mention only a few typical examples. Some of these exist only in some countries: Street prostitution, brothels, private apartment prostitution and nightclubs, “call girl” and “escort” services, “telephone sex”, and internet prostitution.