World map
A map of most or all of Earth's surface.
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A world map is a map of most or all of the surface of Earth. Because of their scale, world maps must deal with the problem of projection, as rendering the three-dimensional Earth in two dimensions necessarily distorts geographic features, distances, and directions. These distortions reach extremes in a world map, and many techniques have been developed to present world maps that address diverse technical and aesthetic goals.
Creating such a map requires global knowledge of the planet’s oceans, continents, and coastlines. For much of human history, from prehistory through the Middle Ages, 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 single culture. Knowledge accumulated rapidly with exploration beginning in the European Renaissance; by the mid-1700s most coastlines were at least roughly charted, and by the twentieth century the continental interiors had been mapped.
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 depict surface characteristics as well as underlying rock, fault lines, and subsurface structures. Choropleth maps use color and intensity to contrast differences between regions, such as demographic or economic statistics. All world maps rely on map projections, methods of representing a globe on a plane, which inevitably distort geographic features, distances, and directions.
The various projections balance accuracy against unavoidable distortion; the Mercator Projection, originally designed as a nautical chart, is perhaps the best known. Thematic maps concentrate on one or a few focused subjects, portraying physical, social, political, cultural, economic, or other aspects. Historical maps, from the Iron Age through the early modern period, reveal not only past geographical knowledge but also the philosophical and cultural bases of cartography, serving as a means for scientists to distribute and preserve ideas.
Quick Facts
- Definition
- Map of most or all of Earth's surface
- Key challenge
- Projection distortion
- Early limitation
- Less than half of Earth's coastlines known before European Renaissance
- Mapping milestone
- Most coastlines mapped by mid-1700s; continental interiors by twentieth century
- Common focus
- Political features or physical features
- Notable projection
- Mercator Projection, originally designed as a nautical chart
Facts from the source article.
Lore & Background
World maps, because of their scale, must deal with the problem of projection. Maps rendered in two dimensions by necessity distort the display of the three-dimensional surface of the Earth. While this is true of any map, these distortions reach extremes in a world map. Many techniques have been developed to present world maps that address diverse technical and aesthetic goals.
Charting a world map requires global knowledge of the Earth, its oceans, and its continents. From prehistory through the Middle Ages, creating an accurate world map would have been 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 that began during the European Renaissance, knowledge of the Earth's surface accumulated rapidly, such that most of the world's coastlines had been mapped, at least roughly, by the mid-1700s and the continental interiors by the twentieth century.
Reader's Guide
World maps serve as fundamental tools for understanding the Earth's surface, yet they are inherently limited by the need for projection. All world maps are based on one of several map projections, or methods of representing a globe on a plane, and all projections distort geographic features, distances, and directions in some way. The various map projections that have been developed provide different ways of balancing accuracy and the unavoidable distortion inherent in making world maps.
Perhaps the best-known projection is the Mercator Projection, originally designed as a nautical chart. World maps generally focus either on political features, such as territorial boundaries and human settlement, or on physical features, such as mountains, soil type, or land use. Geological maps show not only the surface but characteristics of the 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. Thematic maps portray geographical information about one or a few focused subjects, covering physical, social, political, cultural, economic, sociological, agricultural, or any other aspects. Early world maps cover depictions of the world from the Iron Age to the Age of Discovery and the emergence of modern geography during the early modern period, providing information about places known in past times as well as the philosophical and cultural basis of the map.
Frequently Asked Questions
What is a world map?
A world map is a cartographic representation that depicts most or all of Earth's surface. Because it flattens a three-dimensional globe onto a flat plane, it inevitably introduces some degree of distortion in shape, area, distance, or direction.
What is the biggest technical challenge in creating a world map?
The core difficulty is projection distortion—translating a spherical planet onto a two-dimensional surface will always warp geographic features, distances, and directions. Cartographers have developed numerous projection techniques to balance different types of distortion for various practical and aesthetic purposes.
Also in the Codexery
More in Map Projections & Cartography Foundations
Sources
Compiled from Wikipedia and the sources listed below. Text from Wikipedia is available under CC BY-SA 4.0; this entry is adapted from it.
- Wikipedia: World map (CC BY-SA 4.0).
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