Every monk has his "obedience" or tasks assigned by the Hegumen to be done over the course of a day. This may be a one-time task or something very regular.
Obediences are part of the monastic life, and in the East are not considered separately in a sense of a distinction between active/comtepmlative, but simply looked upon as part of the monastic daily life.
It is exactly the same in Western monasticism. Of course the nature of each monk's obedience depends on the work that each monastery does, whether it is education, parish work, manual labour, etc.
