Associated Overviews Introduction Map projections are attempts to portray the surface of the earth or a portion of the earth on a flat surface. Some distortions of conformality, distance, direction, scale, and area always result from this process. Some projections minimize distortions in some of these properties at the expense of maximizing errors in others. Some projection are attempts to only moderately distort all of these properties. When the scale of a map at any point on the map is the same in any direction, the projection is conformal.
Shape is preserved locally on conformal maps.
Distance A map is equidistant when it portrays distances from the center of the projection to any other place on the map. Scale Scale is the relationship between a distance portrayed on a map and the same distance on the Earth. When a map portrays areas over the entire map so that all mapped areas have the same proportional relationship to the areas on the Earth that they represent, the map is an equal-area map. Different map projections result in different spatial relationships between regions. Three Different Map Projections of the United States Albers Equal Area and Lambert Conformal Conic Projections of North America Map projections fall into four general classes.