Equality for lesbian, gay, bisexual and transgender people is today's defining civil rights issue, but the music world has always played a significant role in LGBT progress. With Pride Month here, Billboard reflects on 25 musical moments that have been pivotal in advancing LGBT understanding, acceptance and rights.

Frank Ocean Opens Up About Sexuality

Last July 4, Odd Future member and R&B artist Frank Ocean published an intimate Tumblr post explaining that his first love was a man. The declaration was initially meant to be included in the liner notes to his debut major-label album, "Channel Orange," which came out a week later, but Ocean chose to pre-emptively announce it after a British journalist speculated about the use of the pronoun "he" in love songs like "Bad Religion" and "Forrest Gump." "The night I posted it, I cried like a fucking baby," Ocean told GQ in December. "It was like all the frequency just clicked to a change in my head." (To be clear, Ocean has never publicly defined his sexuality as gay, bisexual or anything else.)

Subsequently, "Channel Orange" was lauded as a major musical accomplishment, earning album of the year at the Soul Train Awards and Grammy nods for album and record of the year, best new artist and best urban contemporary album, the lattermost of which he won-a milestone as the first openly non-straight male in hip-hop and R&B to reach mainstream acclaim. While Ocean's confession garnered support from across the industry--from Beyonce and Jay-Z to executives Russell Simmons and Joie Manda--his accolades proved that the music spoke for itself. --Julianne Escobedo Shepherd

Adam Lambert Glams Up "Idol," Debuts at No. 1

While Adam Lambert didn't make his sexuality a major talking point while competing on "American Idol" -- he later came out in a "Rolling Stone" cover story -- "Idol" viewers and fans at home knew there was something special about the flamboyant contestant. Lambert was out in his personal and professional life well before he hit the "Idol" stage and made his mark as the contestant to watch. On the show, he fired up audiences with his glam rock stylings, sexed-up stage persona and multi-octave range. Though he finished the 2009 season of "Idol" in second place, he remained the season's breakout star and has since worked to become a role model for LGBT teens. His major label debut album "For Your Entertainment" earned him a Grammy Award nomination for the No. 10 Hot 100 hit "Whataya Want From Me," and his sophomore set, "Trespassing," debuted at No. 1 on the Billboard 200 in 2012.  -- Keith Caulfield

Ricky Martin Reveals All in 'Me'

From fresh-faced Menudo sweetheart to "Latin explosion" leader, Ricky Martin has spent much of his career dodging relentless scrutiny over his sexuality. Martin finally put the circus to rest in 2010 and declared himself a "fortunate homosexual man" in an intimate letter to his fans that eloquently described the fear that keeps so many potential gay role models like himself in the closet. "Many people told me: 'Ricky it's not important,' 'it's not worth it. . . all the years you've worked and everything you've built will collapse,'" he wrote. Martin ignored the naysayers and discussed his struggles with his sexuality in his 2010 autobiography 'Me,' which quickly became a New York Times best seller. Martin and his longtime boyfriend Carlos Gonzales are now open and raising twin boys, born to a surrogate in 2008. -- Monica Herrera

NEXT: Against Me!; Jay-Z, Obama

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