So i've been playing with electronics for a year or so.  I've heard about flux a number of times via various sources and I always thought it was just useful for soldering parts together.  However, since all my solder already has some flux in it, I figured buying flux was redundant.  What I didn't realize is how useful & important flux is for de-soldering components- even when using desoldering braid.  Flux is like magic and does an amazing job of helping the braid work a 100 times better.