Latitude constant latitude and constant longitude, which are constructed with reference to the rotation axis of the Earth. The primary reference points are the poles where the axis of rotation of the Earth intersects the reference surface. Planes which contain the rotation axis intersect the surface at the meridians; and the angle between any one meridian plane and that through Greenwich (the Prime Meridian) defines the longitude: meridians are lines of constant longitude. The plane through the centre of the Earth and perpendicular to the rotation axis intersects the surface at a great circle called the Equator. Planes parallel to the
Dell Latitude Dell Latitude Latitude is Dell's business laptop brand, designed and manufactured mainly by Compal and Quanta. The Latitude competes with the ThinkPad series from Lenovo (formerly IBM), the EliteBook series from HP and Travelmate series from Acer. The "Rugged (Extreme)", "XFR" and "ATG" models compete primarily with Panasonic's Toughbook line of rugged computers. The Dell Latitude is a laptop family from Dell Computers, intended for business use. By contrast, the Dell Inspiron is aimed at the consumer market and its specifications change regularly. Whereas Inspiron may change vendors or components several times over the course of a single model, the