What Are Coordinates? A Spatial Reference System

Coordinates are ordered sets of numbers that uniquely identify a point in space. They enable precise location, navigation, and measurement.

Common Systems

• Cartesian (Rectangular): (x, y) in 2D; (x, y, z) in 3D. Axes perpendicular; origin (0,0). Used in math, CAD, graphics.
• Polar (2D) / Spherical / Cylindrical (3D): Distance + angle(s). Used in physics, radar, astronomy.
• Geographic (Lat/Lon): Latitude (−90° to +90°), Longitude (−180° to +180°). WGS84 datum standard for GPS.
• Projected (UTM, State Plane): Flatten Earth to 2D grid (meters); used in mapping, surveying, GIS.
• Celestial: Right ascension/declination (sky coordinates).

Applications

• GPS navigation (lat/lon → map position)
• Surveying & construction (UTM/State Plane)
• Weather modeling (grid points)
• Virtual reality / gaming (Cartesian 3D)
• Robotics / CNC (machine coordinates)
• Astronomy (celestial coords)

Coordinates transform abstract space into computable, communicable locations.