Muhammad Ali, the greatest boxer of all-time and one of the greatest athletes to ever live, has died. He was 74.

Athletes and other celebrities naturally responded with an outpouring of reverence for Ali. Sports Illustrated named him "Sportsman of the Century" in 1999, and he amassed an incredible record of 56-5 with 37 knockouts. His boxing accomplishments are innumerable; he was appropriately nicknamed "The Greatest." 

Beyond the sports world, Ali was known for his activism and devout religious beliefs. He refused to be drafted into the military during the Vietnam War, and was arrested and found guilty of draft evasion charges. He was closely tied with Malcolm X, Elijah Muhammad, and the Nation of Islam, and held his spiritual beliefs throughout his life. He was never afraid to speak his mind, a quality that emboldened many future athletes.

Ali was also known for his inimitable ability to psych out opponents mentally. The trash-talking legend could captivate an audience as well as any athlete who has ever lived. Ali formed rivalries with fellow boxing legends Sonny Liston, Joe Frazier, and George Foreman.

On Thursday, news surfaced that Ali had been hospitalized with a respiratory issue in Phoenix, Ariz., his current hometown. That night, it became clear how ill he had become. His daughter, Laila, posted this photo Friday.

Others, including President Barack Obama, have joined in honoring his memory.

Send all complaints, compliments, and tips to