why do the gold , dollar, currency,stock market & land property values fluctuate

hi there, well that is a very good question to ask i believe many of us out there would like to know why to. Recently i have been trying to understand forex and how to buy and sell currency online to make money. Well but one question that always creeps up in my head in why do they actually fluctuate. I believe by understanding why in fluctuates one can undertstand the market better and eventually make money i hope. Well just as eager you are waiting for the answer so will i. Anyway currently so many people are talking about forex and stuffs, you might wanna check that out. best reagards, alvingb