World map

Lore & Background

World maps require global knowledge of Earth, its oceans, and its continents. From prehistory through the Middle Ages, creating an accurate world map was impossible because less than half of Earth's coastlines and only a small fraction of its continental interiors were known to any culture. With exploration beginning during the European Renaissance, knowledge accumulated rapidly, so that most coastlines were mapped, at least roughly, by the mid-1700s and continental interiors by the twentieth century.

Reader's Guide

World maps generally focus either on political features, such as territorial boundaries and human settlement, or on physical features like mountains, soil type, or land use. Geological maps show not only the surface but also underlying rock, fault lines, and subsurface structures. Choropleth maps use color hue and intensity to contrast differences between regions, such as demographic or economic statistics. All world maps are based on one of several map projections, each distorting geographic features, distances, and directions in some way. The Mercator Projection, originally designed as a nautical chart, is perhaps the best-known projection. Thematic maps portray a focused subject, such as physical, social, political, cultural, economic, or agricultural aspects of a region. Early world maps cover depictions from the Iron Age to the Age of Discovery and the emergence of modern geography, providing information about past known places and the philosophical and cultural basis of the map. Maps are one means by which scientists distribute ideas and pass them on to future generations.

Did You Know?

• World maps must deal with the problem of projection because rendering a three-dimensional surface in two dimensions necessarily distorts it.
• By the mid-1700s, most of the world's coastlines had been mapped, at least roughly.
• The Mercator Projection, originally designed as a nautical chart, is perhaps the best-known map projection.
• Choropleth maps use color hue and intensity to contrast differences between regions, such as demographic or economic statistics.