Morning Musume. (モーニング娘。, Mōningu Musume.?) is an all-girl J-pop group from Japan. They are sometimes also referred to as "Momusu" (モー娘。, Mōmusu.?). Their act revolves around singing and dancing to generally upbeat melodies. They are the lead group of Hello! Project, masterminded by Naoki Yamazaki, and managed by producer Tsunku, who composes nearly all the lyrics and melodies for their songs. Currently, their overall single sales is the highest record of female group on the oricon chart.

Musume (娘, Musume?) in this context, means girl, although the literal meaning is "daughter." The group is particularly well-known for its ever fluctuating line-up, with "graduations" and auditions occurring nearly each year. Over the years there have also been several splinter groups, (including, but not limited to, Tanpopo and Pucchi Moni) and Morning Musume often works closely with other Hello! Project acts, including but not limited to Aya Matsuura, Berryz Kobo, Melon Kinenbi, and v-u-den.

Since their expansion into the Chinese market in 2007, it officially adopted the name Jou An Sao Nu Jou (Zao An Shao Nu Zu) (Traditional Chinese:早安少女組。) in Chinese market.

Source: Wikipedia