The slave system in the Ottoman Empire was very different from that of plantation life in the US and the Caribbean. Males could be either military or domestic slaves and females almost always domestic. Within the gender segregation, there was a racial hierarchy at work, too.
The Islamic world did not operate on a slave system of production, as is said of classical antiquity, but slavery was not entirely domestic either. Slave laborers of various kinds were of some importance in medieval times, especially where large-scale enterprises were involved, and they continued to be into the nineteenth century. The most important slaves, however, those of whom we have the fullest information, were domestic and commercial, and it is they who were the characteristic slaves of the Muslim world. They seem to have been mainly blacks, with some Indians, and some whites. In commerce, slaves were often apprenticed to their masters, sometimes as assistants, sometimes advancing to become agents or even business partners.