Tar Baby is a novel by Toni Morrison about an affair between two African-Americans, Jadine and Son, who come from very different backgrounds. Jadine, a college graduate and successful fashion model is sponsored by the Streets, an elite white family living in the Caribbean. When Son, poor and determined, winds up at the Streets', they begin an affair that disrupts the estate. Together thy travel to the USA, struggling to find a place where they both feel at home. The book examines many of the compromises faced by black Americans.
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Their book summaries aren't as good as other providers, but PinkMonkey often has interesting insights that aren't mentioned elsewhere on the Internet. For example, they go over literary elements (like setting, conflict, and mood), compare and contrast, and symbolism/motifs. It's a good site if you want to find a unique fact or angle that other students don't know about.