A logo (abbreviation of logotype, from Greek: λόγος logos “word” and τύπος typos “imprint”) is a graphic mark, emblem, or symbol commonly used by commercial enterprises, organizations, and even individuals to aid and promote instant public recognition. There are purely graphic emblems, symbols, icons and logos, which are composed of the name of the organisation (a logotype or wordmark).
In the days of hot metal typesetting, a logotype was one word cast as a single piece of type (e.g. “The” in ATF Garamond, as opposed to a ligature, which is two or more letters joined, but not forming a word). By extension, the term was also used for a uniquely set and arranged typeface or colophon. At the level of mass communication and in common usage, a company’s logo is today often synonymous with its trademark or brand.
Numerous inventions and techniques have contributed to the contemporary logo, including cylinder seals (c. 2300 BCE), coins (c. 600 BCE), trans-cultural diffusion of logographic languages, coats of arms, watermarks, silver hallmarks, and the development of printing technology.
As the industrial revolution converted western societies from agrarian to industrial in the 18th and 19th centuries, photography and lithography contributed to the boom of an advertising industry that integrated typography and imagery together on the page. Simultaneously, typography itself was undergoing a revolution of form and expression that expanded beyond the modest, serif typefaces used in books, to bold, ornamental typefaces used on broadsheet posters.