Born Stefani Joanne Angelina Germanotta in New York City, the 25-year-old is one of the loudest voices in pop music. Gaga, best known for her outrageous performances, is also a powerful gay rights advocate. In February, her hit single "Born This Way", which calls on listeners to accept all sexualities, sold a million copies on iTunes in five days, making it the fastest-selling track in the digital music company's history. The singer-songwriter has had two international number-one albums and has been awarded five Grammies. She has also overtaken Justin Bieber and Barack Obama as the world's most prolific microblogger, with 13.6 million "Little Monsters" on Twitter. So prevalent is her cultural influence that the University of South Carolina has developed a sociology course dedicated to her life and works.
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