The name comes from the 1925 Paris Exposition des Arts Décoratifs. It blends optimism about machine-age civilization, a boom of interest in Egyptian and Aztec archaeology, and Jazz Age glamour. New York's Chrysler Building and the exterior ornament of the Empire State Building are its defining examples.
Visually: precise symmetry, stepped-tapering forms (a ziggurat motif), fan-shaped sunburst patterns, and gold or silver metallics set against black, deep green or burgundy. Type runs either bold geometric sans-serif or thin, elongated decorative serifs.
It's used, scoped narrowly, for branding that needs a luxurious, dramatic impression — hotels, casinos, awards shows — and for event pages themed around jazz or cocktail culture. A gold gradient plus a sunburst pattern alone can carry a strong art deco impression.