Compare slavery within Africa by African people

compare slavery within Africa by African people, slavery of Africans instituted by Arabians and perpetuated by Islam, and slavery of Africans by Europeans. How were these forms of slavery similar and different? What types of labor were most punishing on humans? Where might slaves be allowed to develop family ties? Where could they not? How was the rise of global trade and economic pursuits in the 1500s and later a major role in bringing African slaves to the Americas?