Slavery is a system under which people are treated as property to be bought and sold, and are forced to work. 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 most societies; in more recent times, slavery has been outlawed in all countries, but it 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. Slavery is officially illegal in all countries, but there are still an estimated 20 million to 30 million slaves worldwide. Mauritania was the last jurisdiction to officially outlaw slavery, but about 10% to 20% of its population is estimated to live in slavery.
Slavery predates written records and has existed in many cultures. Most slaves today are debt slaves, largely in South Asia, who are under debt bondage incurred by lenders, sometimes even for generations.