The Assumption of Mary into Heaven, often shortened to the Assumption and also known as the Feast of Saint Mary the Virgin, mother of Our Lord Jesus Christ and the Falling Asleep of the Blessed Virgin Mary (the Dormition), according to the beliefs of the Catholic Church, Eastern Orthodoxy, Oriental Orthodoxy, and parts of Anglicanism, was the bodily taking up of the Virgin Mary into Heaven at the end of her earthly life.
The Catholic Church teaches as dogma that the Virgin Mary "having completed the course of her earthly life, was assumed body and soul into heavenly glory". This doctrine was dogmatically defined by Pope Pius XII on 1 November 1950, in the apostolic constitution Munificentissimus Deus by exercising papal infallibility. While the Catholic Church and Eastern Orthodox Church believe in the Dormition of the Theotokos, which is the same as the Assumption, whether Mary had a physical death has not been dogmatically defined.
Happy feast of the Assumption!
Source: Wikipedia.