Tell me and I’ll forget; show me and I may remember; involve me and I’ll understand.
Vigorous writing is concise. A sentence should contain no unnecessary words, a paragraph no unnecessary sentences, for the same reason that a drawing should have no unnecessary lines and a machine no unnecessary parts. This requires not that the writer make all his sentences short, or that he avoid all detail and treat his subjects only in outline, but that every word tell.
Words and pictures are intricately linked in journalism, advertising and educational contexts. Words printed under a photograph, the caption, signal the importance of the common sense representations portrayed in the image. Words beside a picture in an advertisement explain a product and its attributes clearly to a potential customer. Words spoken by an instructor give explanations and life to slides projected from the back of a darkened classroom. Words and images work together for most successful communications.