Writing is the representation of language in a textual medium through the use of a set of signs or symbols (known as a writing system). It is distinguished from illustration, such as cave drawing and painting, and the recording of language via a non-textual medium such as magnetic tape audio.
Tro in: e-Study Guide for: Introductory Chemistry: by Tro, ISBN 9780136003823 , Cram101 Textbook Reviews, 01-Jan-2012, p. 133.