This document provides 20 reasons why a book called "Lessons in Typography" would be useful for designers. It says the book teaches about typefaces as works of art, the language of type, how to make designs using only one or two characters, techniques for modifying type, hidden menus with typographic options, ideas for headlines and logos made of type. It also provides examples combining type and images, how to choose fonts and ensure legibility, alternative ways of presenting paragraphs, and overall design tips for adding type to layouts. The book contains demonstrations, exercises and lessons about typography.