The systems of slavery that has existed in Africa since Ancient times

Describe the systems of slavery that has existed in Africa since Ancient times and how is the slavery system used by Africans and Arabs different from the New World slave systems developed under the Spanish, Dutch, French, and English ? Feel free to also discuss the painful history of the Middle Passage as that connects the two. If you go into great specifics on the Middle Passage then some of the other aspects may be shortened.