B'Day is Beyoncé’s album title styled as a shortened form of “birthday.”
The album was released on September 4, 2006, Beyoncé’s 25th birthday. Its title therefore links the record directly to the date of release and to the celebratory energy of many of its songs.
B'Day was Beyoncé’s second solo studio album, following Dangerously in Love. It produced singles including “Déjà Vu,” featuring Jay-Z, “Irreplaceable,” and “Beautiful Liar,” a duet with Shakira. The album’s sound drew heavily on contemporary R&B, pop, funk, and dance influences.
The apostrophe and capitalization are part of the official styling: B'Day. It is sometimes written casually as “B-Day,” but that is not the album’s canonical title. Beyoncé later released B'Day Deluxe Edition with additional material.