A monk is a man who is a member of a religious order and lives in a monastery. A monk usually lives his life in prayer and contemplation. The concept is ancient and can be seen in many religions and in philosophy.

The Cistercians, officially the Order of Cistercians, are a Catholic religious order of monks and nuns that branched off from the Benedictines and follow the Rule of Saint Benedict, as well as the contributions of the highly-influential Bernard of Clairvaux, known as the Latin Rule. They are also known as Bernardines, after Saint Bernard himself, or as White Monks, in reference to the colour of the "cuculla" or cowl worn by the Cistercians over their habits, as opposed to the black cowl worn by Benedictines.