What are some significant Maya Angelou quotes?

Maya Angelou was an iconic American poet, author, and civil rights activist who penned three essay collections, seven autobiographies, and multiple books of poetry in her lifetime.
Perhaps one of her most famous works is I Know Why the Caged Bird Sings, which details her early years of struggle in attempting to overcome racism and significant trauma in order to transform herself into a woman of great confidence and dignity in the face of cruel prejudice. Within this book, she addresses the experience of being abandoned by her parents and sent to live in Stamps, Arkansas; of being raped at eight years old by her mother's boyfriend; of living on the streets; and of graduating from high school despite becoming a teenage mother. 
The following are two iconic quotes from this autobiography:
"There is no greater agony than bearing an untold story inside you."
"The caged bird sings with a fearful trill, / of things unknown, but longed for still, / and his tune is hear on the distant hill, / for the caged bird sings of freedom."
Angelou also had a penchant for offering fantastic life advice:
"I've learned that people will forget what you said, people will forget what you did, but people will never forget how you made them feel."
"If you don't like something, change it. If you can't change it, change your attitude."
"History, despite its wrenching pain, cannot be unlived, but if faced with courage, need not be lived again."