Slavery is a system under which people are treated as property to be bought and sold, and are forced to work.[1] Slaves can be held against their will from the time of their capture, purchase or birth, and deprived of the right to leave, to refuse to work, or to demand compensation. Historically, slavery was institutionally recognized by many societies; in more recent times slavery has been outlawed in most societies but continues through the practices of debt bondage, indentured servitude, serfdom, domestic servants kept in captivity, certain adoptions in which children are forced to work as slaves, child soldiers, and forced marriage.[2] There are more slaves in the early 21st century than at any previous time but opponents hope slavery can be eradicated within 30 years.[3] Slavery predates written records and has existed in many cultures.[4] The number of slaves today remains as high as 12 million[5] to 27 million.[6][7] Most are debt slaves, largely in South Asia, who are under debt bondage incurred by lenders, sometimes even for generations.[8] Human trafficking is primarily used for forcing women and children into sex industries.[9] In pre-industrial societies, slaves and their labour were economically extremely important. Slaves and serfs made up around three-quarters of the world's population at the beginning of the 19th century.[10] In modern mechanised societies, there is less need for sheer massive manpower; Norbert Wiener wrote that "mechanical labor has most of the economic properties of slave labor, though ... it does not involve the direct demoralizing effects of human cruelty

The English word slave comes from Old French sclave, from the Medieval Latin sclavus, from the Byzantine Greek ???????. The word ???????, in turn, comes from the ethnonym Slav, because in some wars in early mediaeval times many Slavs were captured and enslaved.[12][13] An older theory connected it to the Greek verb skyleuo 'to strip a slain enemy' Chattel slavery, so named because people are treated as the personal property, chattels, of an owner and are bought and sold as commodities, is the original form of slavery. When taking these chattels across national borders it is referred to as human trafficking especially when these slaves provide sexual services.[8] vidence of slavery predates written records, and has existed in many cultures.[4] Prehistoric graves from about 8000 BC in Lower Egypt suggest that a Libyan people enslaved a San-like tribe.[16] Slavery is rare among hunter-gatherer populations, as it is a system of social stratification. Mass slavery also requires economic surpluses and a high population density to be viable. Due to these factors, the practice of slavery would have only proliferated after the invention of agriculture during the Neolithic Revolution about 11,000 years ago.[17] In the earliest known records slavery is treated as an established institution. The Code of Hammurabi (ca. 1760 BC), for example, prescribed death for anyone who helped a slave to escape or who sheltered a fugitive.[18] The Hebrew Bible refers uncritically to slavery as an established institution.[4] Slavery was known in almost every ancient civilization, and society, including Sumer, Ancient Egypt, Ancient China, the Akkadian Empire, Assyria, Ancient India, Ancient Greece, the Roman Empire, the Islamic Caliphate, the Hebrews in Palestine, and the pre-Columbian civilizations of the Americas.[4] Such institutions included debt-slavery, punishment for crime, the enslavement of prisoners of war, child abandonment, and the birth of slave children to slaves