World map

Lore & Background

World maps require global knowledge of Earth's oceans and 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, such that most coastlines were mapped by the mid-1700s and continental interiors by the twentieth century.

Reader's Guide

World maps generally focus on political features (territorial boundaries and human settlement) or physical features (mountains, soil type, land use). Geological maps show surface and subsurface characteristics, while choropleth maps use color to contrast differences between regions, such as demographic or economic statistics. All world maps are based on map projections, which distort geographic features, distances, and directions. The Mercator Projection, originally designed as a nautical chart, is perhaps the best-known projection. Thematic maps portray focused subjects such as physical, social, political, cultural, or economic aspects. Early world maps cover depictions from the Iron Age to the Age of Discovery, providing information about known places and the philosophical and cultural basis of the map, which often differed from modern cartography. 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 the three-dimensional Earth in two dimensions necessarily distorts geographic features.
• From prehistory through the Middle Ages, creating an accurate world map was impossible because less than half of Earth's coastlines were known to any culture.
• Most of the world's coastlines had been mapped, at least roughly, by the mid-1700s.
• The Mercator Projection, originally designed as a nautical chart, is perhaps the best-known map projection.