Brainiac is a fictional character, a DC Comics supervillain and frequent opponent of Superman. Created by Otto Binder, he first appeared in Action Comics #242 (July 1958). Due to complex storylines involving time travel, cloning, and revisions of DC's continuity, several variations of Brainiac have appeared.

Brainiac is a non-fiction narrative by Ken Jennings published in 2006 (ISBN 1-4000-6445-7).

Brainiac was a 1966 toy computer. It was Edmund Berkeley's reduced-cost, lower-functional version of the 1966 Geniac. The Geniac and Brainiac were toys, billed as "computers" (but actually merely rotary-switch construction sets).

Brainiac were an American synth-punk/ indie rock band of the 1990s.