Take an orange and draw something on it -- say, a human face. Now carefully remove the peel, trying to keep it in one piece, and flatten it against your kitchen table. You'll see that in making a two-dimensional object out of a round one, something has to give. Either the face gets distorted and looks all 'mushed out,' or in flattening the peel, it breaks into segments, dividing the face as well into several parts. A cartographer chooses between a series of those kind of lesser-of-two-evils alternatives.
American geographer (1915-2004)
Arthur H. Robinson (January 5, 1915 – October 10, 2004) was an American geographer and cartographer, who was professor in the Geography Department at the University of Wisconsin in Madison from 1947 until he retired in 1980. He was a prolific writer and influential philosopher on cartography, and one of his most notable accomplishments is the in 1961.
From: Wikiquote (CC BY-SA 4.0)
The author took the only course in cartography available to him in 1937; it must have been fairly typical of the few being offered in America: lectures based largely on personal experiences were supplemented by a relatively few assigned readings, and by Deetz and Adam’s Elements of Map Projection. No textbook was used because there was none in English.