A logo (abbreviation of logotype, from Greek: logos "word" and 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 organization (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.
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.
The arts were expanding in purpose-from expression and decoration of an artistic, storytelling nature, to a differentiation of brands and products that the growing middle classes were consuming. Consultancies and trades-groups in the commercial arts were growing and organizing; by 1890, the US had 700 lithographic printing firms employing more than 8,000 people. Artistic credit tended to be assigned to the lithographic company, as opposed to the individual artists who usually performed less important jobs.