Who is the author of I Know Why the Caged Bird Sings?

"I Know Why the Caged Bird Sings" is not a poem, it is a biography of the author of "Caged Bird," Maya Angelou. In the poem, "Caged Bird," the speaker (or narrator) could be anybody, but is most likely Maya Angelou herself, or a colored person in the same situation as the caged bird.