Common GIS Projections

• Mercator -  A conformal, cylindrical projection tangent to the equator. Originally created to display accurate compass bearings for sea travel. An additional feature of this projection is that all local shapes are accurate and clearly defined.
• Transverse Mercator - Similar to the Mercator except that the cylinder is tangent along a meridian instead of the equator. The result is a conformal projection that minimizes distortion along a north - south line, but does not maintain true directions.
• Universal Transverse Mercator(UTM) - Based on a Transverse Mercator projection centered in the middle of zones that are 6 degrees in longitude wide. These zones have been created throughout the world.
• Albers Equal Area Conic -  This conic projection uses two standard parallels to reduce some of the distortion of a projection with one standard parallel. Shape and linear scale distortion are minimized between standard parallels.