What nuns do?

Answer 1

The institution of nuns and sisters, who devote themselves in various religious orders to the practice of a life of perfection, dates from the first ages of the Church, and women may claim with a certain pride that they were the first to embrace the religious state for its own sake, without regard to missionary work and ecclesiastical functions proper to men. St. Paul speaks of widows, who were called to certain kinds of church work (1 Timothy 5:9), and of virgins (1 Cor., vii), whom he praises for their continence and their devotion to the things of the Lord. The virgins were remarkable for their perfect and perpetual chastity which the Catholic Apologists have extolled as a contrast to pagan corruption (St. Justin, "Apol.", I, c. 15; Migne, "P.G.", VI, 350; St. Ambrose, "De Virginibus", Bk. I, C. 4; Migne, "P.L.", XVI, 193). Many also practiced poverty. From the earliest times they were called the spouses of Christ, according to St. Athanasius, the custom of the Church ("Apol. ad Constant.", sec. 33; Migne, "P.G.", XXV, 639). St. Cyprian describes a virgin who had broken her vows as an adulteress ("Ep. 62", Migne, "P.L.", IV, 370). Tertullian distinguishes between those virgins who took the veil publicly in the assembly of the faithful, and others known to God alone; the veil seems to have been simply that of married women. Virgins vowed to the service of God, at first continued to live with their families, but as early as the end of the third century there were community houses known as partheuones; and certainly at the beginning of the same century the virgins formed a special class in the Church, receiving Holy Communion before the laity. The office of Good Friday in which the virgins are mentioned after the porters, and the Litany of the Saints, in which they are invoked with the widows, shows traces of this classification. They were sometimes admitted among the deaconesses for the baptism of adult women and to exercise the functions which St. Paul had reserved for widows of sixty years.

* http://www.newadvent.org/cathen/11164a.htm

Answer 2

Nuns do many different things, depending on their interests and where they are needed. Nuns often act as teachers and caregivers, working in schools, hospitals, orphanages and other places.