BBC Radio 1 is a British national radio station owned and operated by the BBC. It specialises in modern popular music and current chart hits throughout the day. The station provides alternative genres at night, including electronica, dance, hip hop and indie, while its sister station 1Xtra plays black contemporary music, including hip hop and R&B. Radio 1 also runs two online streams, Radio 1 Dance, dedicated to dance music, and Radio 1 Relax, dedicated to chill-out music; both are available to listen only on BBC Sounds.