Timing belts replaced chains because chains are noisier and more expensive to manufacture.  Check your owner's manual to find out at what recommended mileage you should replace your Daewoo timing belt.  Most likely, it will say that you should replace your timing belt between every 60,000 to 105,000 miles.  It's smarter to replace your timing belt at this recommended time than to wait for it to break.  If your timing belt breaks while you're out on the town, you won't be able to drive it.  There are two kinds of engines that utilize timing belts, interference and non-interference engines.  The difference between the engines is the proximity between the pistons and valves.  If the timing belt slips on just one notch on an interference engine, the piston can crash into an open valve causing severe damage to the valves and pistons.  A non-interference engine won't usually be as severely damaged as an interference engine.  Regardless of which engine type you have, if your timing belt breaks, your vehicle will break down.