What's the difference between a cult and a religion? (serious question, don't flame)

a set of beliefs concerning the cause, nature, and purpose of the universe, especially when considered as the creation of a superhuman agency or agencies, usually involving devotional and ritual observances, and often containing a moral code governing the conduct of human affairs.
2.
a specific fundamental set of beliefs and practices generally agreed upon by a number of persons or sects: the Christian religion; the Buddhist religion.
3.
the body of persons adhering to a particular set of beliefs and practices: a world council of religions.

a particular system of religious worship, especially with reference to its rites and ceremonies.
2.
an instance of great veneration of a person, ideal, or thing, especially as manifested by a body of admirers: the physical fitness cult.
3.
the object of such devotion.

Stuff from dictionary.com.