
Cardinal points
There are four cardinal directions or cardinal points: North, South, East, and West, denoted by the initials N, S, E, and W, respectively. On a map, it is common to indicate only the North direction. Cartographers defined the cardinal points and draw maps with the North at the top by convention.
Cardinal points provide a systematic way to tell someone where places are. In cultures that do not descend from European traditions, the cardinal directions could be shown with colours or numbers.
There are many ways to find the cardinal directions: some use the sun or stars, and others the magnetic properties of the Earth (e.g., a compass). Today, satellite navigation (GPS) is widely used.
Cartography
Cartography is the study and creation of maps. Humans have been creating and using maps since early ages in their history. The oldest map that has survived over time is a map of the Babylonian city of Nippur. The technologies used to create maps have evolved a lot since their beginnings.
Mapping started with manual constructions and gradually used new techniques and tools like the compass, telescope, and sextant, increasing the accuracy of maps. In the 20th century, aerial photography and satellite imagery tremendously improved the mapping of physical elements such as buildings, roads, rivers, etc. More recently, GPS can perform direct mapping.
Scales
A scale is a ratio that compares a measurement on a map (or figure) to the actual distance between locations identified on the map (or figure). It's the mathematical relationship between the length or figurative distance on the map and the actual length of the represented distance. Scales have no units. A scale is represented by an ordinary fraction (such as 1 / 1 000 000) or a mathematical ratio (1: 1 000 000). The number 1 means the unit on the map (1 cm) and number 1 000 000 the actual size (1 000 000 cm is about 10 km).
Maps
A map is a simplified representation of populated areas, geographical features, roads, rivers, continents, and oceans. In addition to maps of the Earth and its countries, a city plans or ordnance survey charts are also types of maps. In the past, maps were drawn using a compass, an astrolabe, and a tape measure. Nowadays, they are charted using aerial photography and GPS.
Maps are used for several purposes. The world map shows us countries, large rivers and mountains, the position of oceans and deserts, etc. A country map shows us larger cities and towns, roads, etc. Ordnance survey maps show contours, roads, houses, forests, etc. A city plan shows streets, monuments, parks, etc. All maps show the cardinal points as well as a scale.