For almost as long as there has been civilization, there have been maps -- to record the boundaries of property and territories, to identify landmarks, to show the way to destinations.
Primitive maps grew in sophistication thanks to the ancient Greek invention of geometry, which made possible more accurate measurements of distances. More than 200 years before the Christian era began, Greeks had theorized that the Earth was round and estimated its size within 15 percent of current values.
In Europe's Age of Discovery -- roughly 1500 to 1800 A.D. -- the science of mapmaking advanced explosively as improvements in timekeeping and astronomy led to the development of the latitude and longitude grid system, allowing any spot in the world to be located. Explorers could determine exactly where they were on the grid as they charted new coastlines and lands.
Now, thanks to satellite photography, global information systems and advances in computer technology, cartographers -- both professional and amateur -- are entering what promises to be a new golden age of maps.
Over the last 10 years, the Internet has revolutionized access to mapping tools. Millions print maps and travel directions every day -- all swiftly generated on a half-dozen free and easy-to-access sites.
Global Positioning System units in cars use a network of stationary satellites to guide travel with astonishing precision. Handheld GPS units can locate anyone at any place on the globe, and even allow some techno-geeks to play an increasingly popular and sophisticated form of hide-and-seek.
But that is only the beginning of what is possible with the marriage of maps, computers and the Internet.
Growing numbers of cities and counties across America use satellite photography and sophisticated analytical tools to make real-time assessments of patterns of growth, development and land use.
Third World countries are using the same tools to create plans to limit the potential environmental ravages of rapid economic development and to plan growth to allow the most efficient use of limited infrastructure resources.
These new tools help track bird flu in Asia, prevent crime in Baltimore and manage potentially explosive urban development in China. They promise to multiply the effectiveness of analyses by scientists, economists and public planners.
