1000000 people talking to god is a religion
100000 people talking to god is denomination
10000 people talking to god is a sect
1000 people talking to god is a cult
100 people talking to god is a congregation
10 people talking to god is a prayer circle
1 person talking to god is a paranoid schizophrenic

The difference is a matter of degree. In both the leaders want to control their followers, but cults tend to want to do so to a much greater degree and may not let members leave if they want to.

Time

one commits suicide the other just believe fairytales

Cults are more proactive, smaller & newer.

There really isn't much of a difference. In both, you're told you must follow the teachings of the leader, never question him. The only real difference is that a religion is more widely accepted.

I thought cult was a short version of culture as in cultivating a culture of whatever.
And that cults tend to be extreme and fanatical to their belief and purpose.
There are religious fanatics and extremists cultivating a culture of violence causing terror and fear to mankind.

A cult has fewer followers... I call that a difference but it's largely academic.

This is actually really interesting. I could use more insight on this.

A cult is a small group of people that believe in a perspective that is unaccepted by the culture in which that group of people is a part of. From my perspective.

In the eyes of an atheist nothing, it's all a bunch of crap. I suspect to a theist it's any religion that isn't their religion.