21 is the second studio album by English singer-songwriter Adele. It was released on 24 January 2011 in Europe and on 22 February 2011 in North America by XL Recordings and Columbia Records. The album was named after the age of the singer during its production. 
21 shares the folk and Motown soul influences of her 2008 debut album 19, but was further inspired by the American country and Southern blues music to which she had been exposed during the North American leg of her 2008–09 tour An Evening with Adele. Composed in the aftermath of the singer's separation from her then partner, the album typifies the near dormant tradition of the confessional singer-songwriter in its exploration of heartbreak, introspection, and forgiveness.
Adele began writing 21 in April 2009, when still involved in the relationship that subsequently inspired the record.
Dissatisfied with once again portraying herself as the musical tragedian of her debut, she had intended to compose a more upbeat and contemporary follow-up. However, studio sessions ended prematurely due to a lack of inspiration. She resumed production immediately after the breakdown of her relationship, channelling her heartbreak and depression into her songs.