If I remember right from what I read a few years ago, the difference between "single speed" and "fixed gear" is that one will let you coast (like a normal bike) and the other keeps the pedals moving 100% of the time. Is that accurate? Which is which?
I'm kind of in the market for a new bike and, as FL is nice and flat, I'd consider a ______ (whichever one allows coasting). The simplicity appeals to me.