White smoke means its water turning into seam. There may be a leak somewhere in your car that heats and turns into the smoke. Try checking your rediator.
White "smoke" from your exhaust pipe is water vapor, condensed into visible fog by the cold exhaust system. When it warms up you can't see it any more.
The white smoke may actually be a harmless cloud of moisture condensing when you start your engine; if its truly smoke, it will continue and means you're burning oil.
