Franklin, who began singing in a church choir, had a career that spanned more than six decades, according to CBS News. Her last known performance was in November, for Elton John's AIDS Foundation Fall Gala.
Her career took off in 1967 with the hit song Respect. Franklin's anthemic take on the Otis Redding number won two Grammy Awards. She would go on to win 18 Grammy Awards during her career. She was also the first woman to be inducted into the Rock & Roll Hall of Fame.
Franklin passed away Thursday in Detroit, where she spent most of her childhood and adult life, CBS News reported.
"We mourn the passing of Aretha Franklin, the Queen of Soul," Cook tweeted. "Her voice will keep lifting us, through the music she gave the world. Our thoughts are with her family, her loved ones and fans everywhere. Take her hand, precious Lord, and lead her home," wrote Cook.
Legendary musicians took to Twitter to express their sorrow and to remember Franklin's contributions as both a singer and a person.
"Let's all take a moment to give thanks for the beautiful life of Aretha Franklin, the Queen of our souls, who inspired us all for many many years. She will be missed but the memory of her greatness as a musician and a fine human being will live with us forever. Love Paul," wrote Paul McCartney.
Elton John highlighted one of Franklin's lesser-known talents. "Her voice was unique, her piano playing underrated – she was one of my favourite pianists," the pop star wrote.
The National Association for the Advancement of Colored People paid its respects to the Queen of Soul as "an iconic symbol of black pride whose music touched so many hearts and souls."
Actor Hugh Jackman, known for his role as Marvel action hero Wolverine as well as for his musical talent, said one of the highlights of his career was singing with Franklin at the Tony Awards. He described it as "an out of body experience."
Hillary Clinton mourned on Twitter, as well, saying, "She deserves not only our RESPECT but also our lasting gratitude for opening our eyes, ears and hearts. Rest in eternal peace, my friend."
Star Trek's George Takei said, "She made millions feel like natural women, and she earned our everlasting Respect with each performance. May Aretha Franklin's voice ring now throughout the heavens. She truly was the Queen of Soul. Rest In Peace, o great one."
The term "Blues Brothers" was also trending on Twitter on Thursday in reference to Franklin's scene-stealing cameo role in the 1980 Saturday Night Live-spinoff comedy starring John Belushi and Dan Aykroyd. Her appearance in the film introduced Franklin and her talents to an even wider audience.
One word in particular is associated with Franklin, and that's the title of her most-famous song: Respect. Actress Jamie Lee Curtis shared it as a simple, but powerful tribute: "RESPECT."
Representatives for Franklin didn't immediately respond to requests for comment.
From MP3.com: The best Aretha Franklin song from every decade.
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