Measures of location of any point on the surface with respect to the zero Meridian or Greenwich and the Ecuador. The length is the distance, measured on the parallel passing through that point, between the zero Meridian and that point. It may be length East when that point is located within the 180 degrees East of the zero Meridian or longitude East if you're West of the Meridian. Latitude is the distance, measured along the Meridian that passes by that point, between the Equator and that point may be North latitude and latitude South, according to which that point is in the northern hemisphere or in the South. These measures are established in sexagesimal degrees, minutes and seconds. The degrees of latitude ( 41 90; they amount to little more than 111 Km; one minute, more than 1855 m and a second, almost 31 m. The degrees of longitude are variable according to the latitude because the Earth is wider at the equator.