What is the difference between civil unrest and civil war?

[Cole M]

As many, if not most people know, there is conflict between the Iranian government and the people that reside within Iran currently. Such a conflict might have been brewing for a while, but as far as I know the most recent conflict between the Iranian government and its people sparked when Mahmoud Ahmadinejad ( I think this is how is name is spelled, if memory serves correctly) had questionably won. Anyways I come back to my question, as the above serves only as my particular thought on the subject. I came here pondering is there a line to draw between civil unrest and civil war? If so, what are the guidelines of the crossing from unrest to civil war. Also is Iran in a period of civil war or unrest? This question merely comes from curiosity, so if anyone could specify or elaborate on their answer, I would be very pleased...