<P> Cartography or map - making is the study and practice of crafting representations of the Earth upon a flat surface (see History of cartography), and one who makes maps is called a cartographer . </P> <P> 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 . 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: a civilian government agency, internationally renowned for its comprehensively detailed work . </P> <P> In addition to location information maps may also be used to portray contour lines indicating constant values of elevation, temperature, rainfall, etc . </P> <P> The orientation of a map is the relationship between the directions on the map and the corresponding compass directions in reality . The word "orient" is derived from Latin oriens, meaning East . In the Middle Ages many maps, including the T and O maps, were drawn with East at the top (meaning that the direction "up" on the map corresponds to East on the compass). Today, the most common--but far from universal--cartographic convention is that North is at the top of a map . Several kinds of maps are often traditionally not oriented with North at the top: </P>

Maps are drawn to blank to represent an actual place that is much larger