The boxing legend, 74, was notable for a long career both in and out of the ring, serving as an iconic talker both for himself and for racial equality.
His first major professional bout was against Sonny Liston, the then-heavyweight champion of the world. Ali compared Liston to a "big ugly bear" and said he would "float like a butterfly and sting like a bee."
"Liston even smells like a bear," Ali said. "After I beat him I'm going to donate him to the zoo." Thus began his fame for being quotable, on all topics..
The next most famous opponent Ali faced was the United States government. On June 20, 1967, Ali was convicted of draft evasion after he refused to be drafted into military service during the Vietnam War.
"I ain't got nothing against no Vietcong; no Vietcong never called me nigger," Ali famously said.
It was four years, all during his prime, before the Supreme Court overturned his conviction in 1971. Ali was 29.
A few of his more memorable quotes:
On Joe Frazier
"Frazier is too ugly to be champ," Ali said of his opponent. "Frazier is too dumb to be champ."
On preparing for his fight George Foreman:
"I'm so mean I make medicine sick"
On his boxing skills:
"If you even dream of beating me you'd better wake up and apologize."
Ali was diagnosed with Parkinson's disease, a disease that can result from repeated trauma to the head, in 1984.
Ali is survived by nine children, two ex-wives, and widow Yolonda.
Our thoughts are with them.