We reflect on 20 musical moments that were pivotal in advancing the understanding and acceptance of lesbian, gay, bisexual and transgender people.

Kurt Meets Blaine on "Glee"

If ever there was a moment where a collective audience cried "squee!" into their Tumblrs and Twitter accounts at the same time, it was when "Glee's" out-gay teen Kurt Hummel met the swoontastic (and equally out) Blaine Anderson in 2010. It helped that Blaine essentially serenaded Kurt -- and the "Glee" viewers at home -- with an all-male a capella rendition of Katy Perry's "Teenage Dream." The meeting not only launched a landmark prime-time teen gay romance (including a buzzed-about kiss in March 2011), but a lauded storyline about bullying. As a bonus, the "Glee" cast earned its best single sales week for a download with the release of "Teenage Dream" (214,000) -- a record the cast has yet to break. -- 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

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