DPI most generally refers to Dots Per Inch, a term applied to printing resolution. Specifically, it identifies the number of dots a printer can place on a page in one inch. Higher DPI means more detail and definition in a printed page. A related term, PPI, or Pixels Per Inch, is applied to video screens.
The longitude specifies the location's distance east or west from an imaginary line connecting the North and South Poles, called the Prime Meridian. Latitude and longitude are used together to specify the geographical coordinates of a location on Earth.
The distance between degrees of longitude is about 60 nautical miles at the equator. It is less further north or south as the longitude lines converge towards the poles. Degrees of latitude are always 60 nautical miles apart. At the equator, a grid of 1Â° of longitude by 1Â° of latitude covers about 3,600 square miles. For greater precision, degrees are divided into 60 minutes ( ' ) - of distance, not time.