Latitude and longitude are descriptions of the location, or geographic coordinates, from a certain place on Earth. How latitude is set depends on the reference surface used, and longitude is measured in degrees, from zero to 180 east or west from the Greenwich Meridian, and there is no natural starting position to mark the longitude.
Latitude is the angle between the plane of the equator and the reference surface. Latitude is measured north and south of the equator, between 90° south at the South Pole and 90° north at the North Pole. Latitude is the distance to the Equator measured along the Greenwich meridian, this distance is measured in degrees, and it can vary between 0º (at the equator) and 90º to the North or to the South.
On the other hand, longitude is measured along the equator, and represents the distance between a point and the Greenwich meridian. It is also measured in degrees, ranging from 0º to 180º to the East or West.
Longitude measurement is important for both cartography and safe ocean navigation. Throughout history, many explorers have struggled to find a method of determining longitude, like Americo Vespucci and Galileo. However, the calculation of longitude has always presented serious problems, especially on the high seas. Determining latitude is simpler, just measure the angle between the horizon and the North Star with the help of a quadrant, astrolabe or sextant.
Our position on Earth is referenced in relation to the equator and the Greenwich meridian and is based on three denominations: a latitude, longitude and altitude.
The latitude and longitude of Brasília (the Brazilian capital) is 15° 46′ 47″ South, 47° 55′ 47″ West.
See too: Types of maps.