There are Fluorocarbon lines and Fluorocarbon coated lines ( Mono ), which also have a reason for existing. Not all makers of Fluorocarbon coated lines make that distinction clear in their product literature and I think it's helpful to know what you're shopping for and purchasing.

http://flyanglersonline.com/about/seaguar/

For starters, here's a link to a Q & A section provided by Seaguar about the production, properties and characteristics of Fluorocarbon, that might help fill in some of the gaps.

http://seaguar.com/seaguar-community/fishing-line-q-and-a.htm

Enjoy, Dave