Chapter 1 WHAT ARE ROAD MAPS AND GPS This amazing world of ours offers so much to see Maps can help us find our way Maps use symbols to represent places and the living or nonliving things there They let us locate these things in our environment This family uses a map while on a road trip How can maps help
WISCONSIN MICHIGAN men ROOOR IONA Cartographers or mapmakers design maps for certain purposes Some maps mark borders of cities or countries Others display facts about a place such as how many people live there Still others focus on roads and highways the main roads in an area These are called road maps They help people find their way from one location to another This road map shows major roads in
Modern Road Maps At one time all road maps were printed on paper These maps were large and had to be folded for storage when not in use These days many road maps are on cell phones and other devices These maps can change as roads change For example if a road were closed for construction the map might update itself to show that These maps can also pinpoint where you are by using sensors in the device Maps like this are part of the Global Positioning System or GPS GPS is a system that uses signals from satellites to tell you where you are and to give you directions to other places O GPS is behind the mapped routes that smartphones plot
Early GPS Satellites are human made objects that people send into space to circle Earth other planets and the moon They can send signals to devices such as cell phones Satellites are a fairly old technology The first GPS satellite launched in 1978 for the military President Ronald Reagan made GPS free to the public in 1983 Russia India China and other countries hope to launch similar systems This illustration shows what a satellite looks
