The answer to 'what is navigation?' is, shortly given as the help to change position around the world from one place to another.In the other words when we use navigation technology we are aware of the way we go to the place we want and the place that we are now. Mankind's earliest navigational experiences started even before the birth of Christ. Ancient mariners, bronze age Minoan seamen and later Vikings were probably making infrequent journeys across oceans in different routes. Of corse everybody wants to answer the question: how did they find their way across boundlessseas without any piece of integratng accelerometers and hand-held recievers which are available in commercial markets today? Normally there are still dozens of ships which were sent to the bottom by numerous navigational errors; than a new technology of radionavigation become widespread especially dıring the World War II also in military sector. In the following years many countries espacially U.S.A have operated ground-based radionavigation systems and started to move their navigational transmitters upward from the surface of the earth into outher space to get more accuracy despite the astronomical costs. The Global Positioning System (G.P.S.) is one of the most important inventions of the last century, which uses the future's preferred technology of sattelites and radionavigation, and has many applications an both the civil and military sectors.