

Equal-area Projections are projections that maintain the same proportional relationship to the corresponding areas on the Earth, although shape may not be preserved, especially at high latitudes. In the Mollweide Projection, the Earth is projected onto a 2:1 ellipse, where the equator is twice the length of the central meridian. The parallels are straight, but are compressed near the poles, while the aside from the central meridian, the meridians are projected as elliptical arcs equally spaced at the equator. This results in the elongation of shapes in the north-south direction, especially towards the poles. In addition, scale is only true along the standard parallels and according to the Mollweide Projection, the distance from Washington D.C. to Baghdad is approximately 6,600 miles.
Like the Mollweide Projection, in the Sinusoidal Projection, shapes are increasingly distorted away from the central meridian and near the poles. In the Sinusoidal Projection, the polar region is overcrowded, while the Mollweide Projection spaces the meridians, but creates more extreme angular distortion. The Sinusoidal Projection is a pseudo-cylindrical projection that preserves not only area, but distances along the horizontals. According to the projection, the distance from Washington D.C. to Baghdad is approximately 6,700 miles, which is fairly reasonable compared to the actual distance of 6,200 miles, and may have to do with the fact Washington D.C. and Baghdad are located on nearby parallels.
Equidistant Projections show distances from the center of the projection to be equidistant to any other place on the map in all directions. In the Equidistant Cylindrical Projection, all meridians are equally spaced straight vertical lines and all parallels are equally spaced straight horizontal lines. The scale is true and therefore equidistant along all the meridians, however because the poles are represented as straight lines equal in length to the equator, distortion of both shape and area increases towards the poles. According to the Equidistant Cylindrical Projection, the distance from Washington D.C. to Baghdad is approximately 4,200 miles, over 2,000 miles shorter than the actual.
In the Equidistant Conic Projection, distances are true along the meridians and one or two standard parallels, and distortion increases away from the standard parallels. In this map, areas north of the equator are well represented in direction, shape and area. According to the projection, the distance from Washington D.C. to Baghdad is approximately 6,300 miles, almost identical to the actual distance of 6,200 miles. However, the map is extremely distorted south of the equator, showing Australia as similar in size to North America.