Earth has a curved surface, but most maps are displayed on a flat screen or sheet of paper. Map projection is the mathematical method used to transform Earth’s three-dimensional surface into a two-dimensional map.

Turning a Globe into a Flat Map

A globe naturally represents the shape of Earth, but it is not always practical for measurement, navigation, or geographic analysis. Map projections allow geographic coordinates and features to be represented on a flat surface while maintaining specific properties as accurately as possible.

Why Does Distortion Occur?

Because a curved surface cannot be flattened perfectly, every map projection introduces some form of distortion. The shape, area, distance, or direction of geographic features may change depending on the projection.

Different Projections, Different Results

Map projections are designed for different purposes. Some prioritize preserving shape and angles, while others focus on area, distance, or direction. As a result, the same region can appear differently when represented using different projections.

Choosing the Right Projection

The appropriate projection depends on the purpose and geographic extent of a map. A projection designed for navigation may not be suitable for comparing land areas, while a global map may require a different approach from a detailed regional map.

Why It Matters

Map projection is more than simply changing a globe into a flat image. It directly influences how geographic information is represented and interpreted. Understanding the projection behind a map helps users recognize its limitations and make more accurate spatial analyses.

A map is never just a picture of Earth—it is a mathematical representation of it.