The word cult comes from Latin cultus, "worship," from past participle of colere, "to cultivate." This short course explains what a cult is, and discusses many types of cults: Christian, Muslim, Buddhist, Gnostic, etc., and how we worship according to our inner psychological and spiritual state. Every spiritual person is engaged in worship (cult), but our psychological state determines whether that worship results in benefit or harm. This is a lecture from the free online course Heavenly and Satanic Cults: Types of Spiritual Groups