This document discusses the use and purpose of lines in design. It identifies six main types of lines: outlines, contour lines, gesture lines, sketch lines, calligraphic lines, and implied lines. Each type of line serves a different visual purpose. The document also discusses characteristics of lines like width, length, direction, and feeling. Lines in design are used to divide space, direct the eye, separate content, emphasize elements, link items, and coordinate flow. Understanding how to effectively employ lines is important for design as it helps attract attention, organize information, and achieve desired outcomes. The document provides examples of logos that incorporate different types of lines and their purposes. It presents an exercise for enhancing an existing logo design by adding