A GPS unit provides precise latitude and longitude for the location of the device. By using a hand-held GPS unit along with a map that provides latitude and longitude (such as a topographic map), you can determine your precise location on the Earth’s surface. This is a valuable tool for those who hike or travel in remote regions and for ships at sea. GPS is now widely available in cars; as stand-alone, portable, pocket-sized devices; on cell phones; and even on the boxes that ship products that you buy. In short, GPS is used in all aspects of our lives.