Hobbies And Interests
Unprojected
An unprojected map is a grid-style map, where the map is based on a simple longitude and latitude system. The various lines are all at right angles. A map like this is easier to read, but is not an accurate representation of the Earth. Unprojected acreage, then, will be easier to understand and read, but will not necessarily be an accurate representation of the total size of the acreage.
Projected
A projected map is the more accurate of projected and unprojected. A projected map follows the contours of the Earth, and the proper longitude and latitude lines. Projected measurements are more accurate, and most professional maps will be done in projected form, rather than unprojected. To get an accurate idea of the size and shape of acreage, projected maps and data are what you need to use.
Equator
One interesting feature of the projected and unprojected systems of mapping is that there will be little to no difference between the two systems at one place, which is the equator. As you move farther away from the equator, however, the tapering of the Earth becomes more pronounced, and this causes the grids formed by longitude and latitude lines to squeeze together and stretch out, making unprojected maps less and less accurate.
Other Uses
Projected and unprojected data is useful for calculating acreage size, as well as the borders of that acreage. This is especially true when the acreage in question is large, and the differences between the two systems are more pronounced. But this is hardly the only use of projected and unprojected data. The military has many uses for the two different systems, as do most other government agencies and private organizations and individuals that rely on accurate map data.