Katy Perry could really hear her fans 'Roar' last night ... probably screaming out in horrible pain -- 'cause one of them ...

Although Katy Perry is best-known for frothy, off-the-walls pop music, the Billboard Hot 100 topper opened her Thursday (Jan.

UNICEF released this video with Katy Perry to highlight the issue. Even though more girls are entering school than ever before, 31 million are still denied this right. The world needs new ...