Latitude ( or ). It is measured in degrees, minutes and seconds or decimal degrees, north or south of the equator. The precise measurement of latitude requires an understanding of the gravitational field of the Earth, either to set up theodolites or to determine GPS satellite orbits. The study of the figure of the Earth together with its gravitational field is the science of geodesy. This article relates to coordinate systems for the Earth: it may be extended to cover the Moon, planets and other celestial objects by a simple change of nomenclature. The graticule is formed by the lines of
Dell Latitude the C6x0, D6x0, and E64x0 lines, but as of 2015 this line has been discontinued and replaced by both the 5 series and the 7 series. The 15" "Premium" line was the 8 series, until the E-series merged this line with the 6 series (Model numbers being along the lines of C8x0 or D8x0). The "budget" line was the 5 series, but as of 2015 the 5 series and 7 series Latitude laptops are the primary lines of Latitude laptops. The 3 series has replaced the 5 series as the budget line. Dell has also since dropped the E from