If we don't change our direction, we are likely to end up where were headed. - Chinese Proverb

Modern Methods

Dead Reckoning: Is the process of estimating a global position of a vehicle by advancing a known position using course, speed, time and distance to be traveled. That is, in other words, figuring out where you momentarily are or where you will be at a certain time if you hold the speed, time and course you plan to travel.

Pilotage: Is the use of fixed visual references on the ground or sea by means of sight or radar to guide oneself to a destination. Pilotage is used by people guiding vessels and aircraft, by hikers and SCUBA divers.

Celestial Navigation:Uses angular measurements between the horizon and a common celestial object. The Sun is most often measured. The Moon, planets or one of 57 "navigational stars" that are described in nautical almanacs can also be used.

Radio Navigation: Uses radio frequencies for determining a position. By tuning in a radio station and then using a directional antenna to find the direction to the broadcasting antenna. Taking two such measurements and plotting the directions on a map will result in an intersection, your current location.

GPS: The Global Positioning System, is the Earth's only fully-functional satellite navigation system. A constellation of more than two dozen GPS satellites broadcasts precise timing signals by radio.