21 is the second studio album by English singer-songwriter Adele. Released on 21 January 2011 in the UK and most of Europe, and on 22 February 2011 in North America, the album was named after the age of the singer at the time of its production. While it relies heavily on the folk and Motown influences that framed her debut 19, the album also explores various genres and styles from country and blues to alternative pop, indie-rock, and R&B. 21 is a break-up album, with songs exploring aspects of the singer's most recently ended relationship.
The majority of the album's production was handled by Grammy Award-winning American producer Rick Rubin, with additional producers including Jim Abbiss, Paul Epworth, Fraser T. Smith, Ryan Tedder and Dan Wilson. Released to positive reviews, critics complimented Adele's vocal performance and introspective songwriting. Preceded by lead single "Rolling in the Deep", 21 debuted at number one on the UK Album Chart with first-week sales of 208,000 copies. It also debuted at number one in over ten countries, including Canada, Germany and Ireland. In the U.S., the album debuted at number one on the Billboard 200 chart, selling 352,000 copies in its first week.
Following a well-received performance of the album's second single "Someone Like You" at the 2011 BRIT Awards, the album maintained its number one position in the UK for eleven consecutive weeks, before being dethroned by the Foo Fighters' Wasting Light on the week of 17 April 2011. However, 21 returned to the top spot the following week, and as of July 2011, has spent a total of seventeen aggregate weeks at number one. The album's eleven-week consecutive run at the top broke the record for the longest running consecutive number-one studio album for a solo artist. It also became the biggest-selling digital album of all-time in the UK. 21 has been certified 10-times platinum by the British Phonographic Industry, denoting domestic shipments in excess of three million units. A third single, "Set Fire to the Rain", attained success across several European territories and has peaked at number eighty-eight on Billboard thus far. In the U.S., the album spent ten non-consecutive weeks at number one, and has sold over 2.6 million copies. Total worldwide sales have surpassed eight million copies, making 21 the best-selling album of the year so far.
