Legendary American singer Tony Bennett dies at age 96

Bennett revealed in early 2021 that he was diagnosed with Alzheimer’s Disease in 2016, but he kept recording

Tony Bennett, the smooth American singer who had an enduring hit with "I Left My Heart in San Francisco" and remained perpetually cool enough to win over younger generations of fans well into the 21st century, has died at the age of 96, the Associated Press reported Friday.

No less than Frank Sinatra called the former singing waiter "the best singer in the business" after he became a star in the 1950s. Bennett went on to win 20 Grammy awards, including a lifetime achievement award.

The older he grew, the more diverse his collaborators became. Bennett was in his late 80s when he recorded a 2014 album of duets with the outre Lady Gaga and went on a world tour with her in 2015. Partners on his popular "Duet" albums ranged from former Beatle Paul McCartney and soul queen Aretha Franklin to country star Willie Nelson and U2's Bono.

Bennett marked his 90th birthday in 2016 with a party in New York that drew celebrities such as Bruce Willis and John Travolta. The Empire State Building put on a light show in his honor. He also published a memoir in 2016 titled "Just Getting Started."

Bennett revealed in early 2021 that he was diagnosed with Alzheimer's Disease in 2016, but he kept recording after the diagnosis and later tweeted, "Life is a gift - even with Alzheimer's."

Due to his illness, Bennett retired from performing after his final concert at Radio City Music Hall On August 3 and 5, 2021.

Bennett's career was filled with highs and lows.