The earth is round, but a map is flat. How do you get an object that has 3 dimensions onto a 2 dimensional surface? Map projections and the mathematics behind them show you how. But because you are losing a dimension, you also lose an element of the visual representation. Depending on the projection used, the viewer loses at least 1 of the following: direction, shape, area or distance.
An earlier edition of A Dictionary of Geography defines projection as "a technique for transforming the three-dimensional sphere of the earth into the two dimensions of a map. There are four aspects of the map to be considered: area, distance, direction, and shape, and it is impossible to recreate them all in the same map. See map projection.
Want an easy way to keep up with the journal literature for Cartography or GIS? And do you use a mobile device? You can install the BrowZine app and create a custom Bookshelf of your favorite journal titles. Then you will get the Table of Contents (ToCs) of your favorite journals automatically delivered to you when they become available. Once you have the ToC's, you can download and read the articles you want from the journals for which we have subscriptions.
You can get the app from the App Store or Google Play.
Don't own or use a mobile device? You can still use BrowZine! It's now available in a web version. You can get to it here. The web version works the same way as the app version. Find the journals you like, create a custom Bookshelf, get ToCs and read the articles you want.