God calls each of us to a particular vocation in life. The Catholic Church defines both particular vocations as three states of life: single, married, religious, and also a general vocation of all baptized believers.
There are many roles within the Catholic Church for both ordained and non-ordained people. A non-ordained person is typically referred to as a lay person, or one who is not a member of the clergy. One who is ordained is someone who has received the sacrament of Holy Orders.