''B'Day'' is the second studio album by American R&B singer Beyoncé Knowles, released September 4, 2006, on Columbia Records in collaboration with Music World Music and Sony Urban Music. Its release coincided with Knowles' twenty-fifth birthday. The album was originally planned for a 2004 release as a follow-up to her debut album ''Dangerously in Love'' (2003). However, the project was put on hiatus due to the recording of Destiny's Child's final studio album ''Destiny Fulfilled'' and her starring role in the 2006 movie ''Dreamgirls''.

While on vacation after filming for ''Dreamgirls'', Knowles began contacting various producers; she had employed technique for faster collaboration, and completed ''B'Day'' in three weeks. Most of the lyrical content of the album was inspired by Knowles' role in the film. The album's musical style ranges from '70s to '80s funk and balladry to urban contemporary elements such as hip hop and R&B. Live instrumentation was employed on most tracks as part of Knowles' vision of creating a record using live instruments.

The album debuted at number one on the U.S. ''Billboard'' 200 chart, selling 541,000 copies in its first week, and it has been certified triple platinum in sales by the RIAA. It was also successful in international music markets and yielded six singles, including three worldwide hits, "Déjà Vu", "Irreplaceable", and "Beautiful Liar". Upon its release, ''B'Day'' received generally positive reviews from most music critics and earned Knowles several accolades, including a Grammy Award for Best Contemporary R&B Album at the 49th Grammy Awards. - Wikipedia