21 - Adele

Adele's second studio album, 21 is her second studio album. It was released by XL Recordings in Europe on January 24, 2011, and Columbia Records in North America on February 22, 2011. The album was named after the singer's age at the time of its creation. 21 shares the Motown/soul influences of her 2008 debut album 19, but also draws influence from American country and Southern blues music, which Adele discovered during the North American leg of her tour An Evening with Adele. The album was written in the aftermath of the singer's divorce from her then-partner, and it explores themes of heartbreak, healing, introspection, and forgiveness.

21 was nominated for the 2011 Mercury Prize and won the 2012 Grammy Award for Album of the Year as well as the Brit Award for British Album of the Year. It was praised for its understated production, vintage aesthetic, and Adele's vocal performance. It has since been named one of the 500 Greatest Albums of All Time by Rolling Stone and is included in the book 1001 Albums You Must Hear Before You Die.

Estimated sales: 31 million