 Share facts or photos of intriguing scientific phenomena. # Longitude Vs. Latitude Geographic Coordinate System

Longitudes and latitudes are useful to locate any point on the surface of the Earth. This ScienceStruck article sheds more light on this calibration system and its immense use to mankind.
Anand Karwa
 The headquarters of Facebook are located at 37.484619, -122.148619. If you don't know what these decimal numbers mean, then you should read this ScienceStruck article to get yourself acquainted with longitudes and latitudes

Like we all know, a coordinate system is used to determine the location of any point in a two-dimensional plane. For plotting points in x, y, and z planes, we use Cartesian coordinate system. Similarly, we use geographic coordinate system for finding out the location of any point on the surface of the Earth.
Longitudes and latitudes are used to describe the exact location of any point in the geographic coordinate system, but one can often get confused between longitudes and latitudes. This ScienceStruck article will try to understand the difference between longitude vs latitude coordinate system. We will also explain how to express the location of any point in terms or longitude and latitude.
Meridians
These are imaginary lines running between the geographical poles of the Earth. All meridians are equal in length. A meridian can also be defined as an imaginary line joining points having same longitudes. A meridian passing through the Royal Observatory, Greenwich, London is known as the Prime Meridian. It is accepted as a reference meridian and is also known as zero-longitude reference line.
Parallels
These are imaginary circles parallel to the equator. Equator is the longest parallel, and hence, is taken as a reference (zero latitude line) for describing the latitude of any place on the Earth. The length of parallels goes on decreasing towards the poles. The parallels at the poles are point circles.
Longitude
The longitude of a point is defined as the angle formed by the Prime Meridian and the median passing through that point. The angle is described in either East or West, with 0 to180 degrees for the East, and 0 to -180 degrees for the West.
Latitude
The latitude of a point is described as the angle between the equatorial plane and the line connecting that point to the center of the Earth. This angular measurement is described using North and South angles. +90 and -90 degrees are used to represent the North and South poles, respectively.
Representation of the Coordinates
Angular measurement is always done in degrees (°), minutes (') and seconds ("). Given below are the coordinates of Los Angeles in 3 commonly used systems:
• Degrees, Minutes and Seconds: 34°03′08″ N 118°14′37″ W
• Degrees and decimal Minutes: 34°3.1338′ N 118°14.6208′ W
• Decimal degrees: 34.0522300° -118.2436800°
Applications
These coordinate systems are extensively used in: