Human beings have developed maps of the world around them for centuries. These maps are reflections of how we visualize our surroundings. The art of developing maps has advanced with the advancement in technology and especially with the emergence of satellite imagery. Different projections depict different ways of portraying the earth with the best possible accuracy in scale. There exists a vast number of world map projections and here are the most commonly used.
Cylindrical Map Projections
Cylindrical maps are actually rectangular in shape only that they can be folded into a cylinder to represent the actual shape of the earth. They consist of parallel latitudes and longitudes meeting at 90 degrees. Their main disadvantage is that they produce accurate information only for the area around the equator. The areas around the poles are greatly distorted. The most popular cylindrical map is the Mercator projection. Others include Cassini, Miler, Behrman and the Gauss- Kruger.
Conic Map Projections
These maps have parallel latitudes which cross at right angles with the meridian. They have constant distortion throughout to cater for the curvature. This distortion is referred to as the cone constant. They can be rolled up on a globe to give a true virtual representative of the earth though not with geometrical accuracy. They cannot be used as a visual of the entire earth due to the distortion. They produce great visualization when used to show climate projections, temperate regions and as weather maps. A good example of a conic map is the Albers projection. Other examples are Lambert conformal conic and the Equidistant conic projection.
Azimuthal Map Projection
Azimuthal are great for knowing the direction from anywhere on the earth with the central point being used as the reference. This is mainly attributed to the fact that they have angular relationships. These relationships can be referred to as geodesic arcs or great circle arcs. A popular example of the azimuthal is the Lambert azimuthal equal-area projection.