Map

A map is a simplified depiction of a space, a navigational aid which highlights relations between objects within that space. Most usually a map is a two-dimensional, geometrically accurate representation of a three-dimensional space. The science and art of map-making is cartography.

Map-making dates back to the Stone Age and appears to predate written language by several millennia. One of the oldest surviving maps is painted on a wall of the Catal Huyuk settlement in south-central Anatolia (now Turkey); it dates from about 6200 BC.

While we tend to think of maps today as products of a rationalistic, scientific world-view, maps also have a mythic quality. Pre-modern maps, and mapping traditions outside the Western tradition, often merge geography with non-scientific cosmography, showing the relationship of the viewer to the universe. Medieval "T-O" maps, for example, show Jerusalem at the centre of the world, and in some cases related the "body" of the Earth to the body of Christ. By contrast, navigational (or "Portolan") charts of the Mediterranean from the same period are remarkably accurate. Even today, maps can be powerful rhetorical tools beyond their purely practical value, and this has been the source of much fruitful map criticism over the last twenty years, notably in the works of J.B. Harley, Mark Monmonier, and Denis Wood.

Because maps are abstract representations of the world, they are not neutral documents and must be carefully interpreted. It is, of course, this abstraction that makes them useful. Lewis Carroll made this point humorously in Sylvie and Bruno with his mention of a fictional map that had "the scale of a mile to the mile". A character notes some practical difficulties with this map and states that "we now use the country itself, as its own map, and I assure you it does nearly as well". This conceit is elaborated in a one-paragraph story by Jorge Luis Borges and Adolfo Bioy Casares, generally known in English as "On Exactitude in Science".

Road maps are perhaps the most widely used maps today, and form a subset of navigational maps, which also include aeronautical and nautical charts, railroad network maps, and hiking and bicycling maps. Community maps, including GreenMaps, are growing in importance. In terms of quantity, the largest number of drawn map sheets is probably made up by local surveys, carried out by municipalities, utilities, tax assessors, emergency services providers, and other local agencies. Many national surveying projects have been carried out by the military, such as the British Ordnance Survey (now a civilian government agency internationally renowned for its comprehensively detailed work).

Orientation of maps

Conventionally, on most geometrically accurate maps text is upright when the map is oriented with the north up, hence north is identified with the top of a sheet.

Maps that don't put north at the top:

Polar maps
Dymaxion maps

Some rectangular maps produced in Australia show the south pole at the top. To someone used to seeing the map the other way around, this map may appear to be "upside down". These are primarily intended as novelty and tourist maps.

Other modern maps put south on top, generally either out of a sense of playful confusion or to make a political statement about the North-South divide.

Old maps of Edo show the Japanese imperial palace as the "top," but also at the centre, of the map. Labels on the map are oriented in such a way that you cannot read them properly unless you put the imperial palace above your head. Medieval European T and O maps such as the Hereford Mappa Mundi were centred on Jerusalem, with East at the top.

If a person is located at an identifiable point within the area of such a map, then the map can be oriented in such a way that every point on the map lies in the same direction as the corresponding point in reality. The practice of navigating in this way is orienteering.

For a vertically positioned map representing a horizontal area true orientation is not possible, of course, but it is sometimes approximated by putting the forward direction up.

Occasionally a map is on a ceiling, correctly showing directions; in that case, looking up we have in clockwise direction forward, left, backward, and right. If the map is prepared on a table, to be attached to the ceiling, then on the table it is a mirror image of a normal map.