Venom is a fictional character appearing in American comic books published by Marvel Comics, commonly in association with Spider-Man. The character is a sentient alien symbiote with an amorphous, liquid-like form, who survives by bonding with a host, usually human. This dual-life form receives enhanced powers and usually refers to itself as Venom. The symbiote was originally introduced as a living alien costume in The Amazing Spider-Man #252 (May 1984), with a full first appearance as Venom in The Amazing Spider-Man #300 (May 1988).

The Venom symbiote's first human host was Spider-Man himself, who eventually discovered its true nefarious nature and separated himself from the creature in The Amazing Spider-Man #258 (November 1984)[2] — with a brief rejoining five months later in Web of Spider-Man #1.[3] The symbiote went on to merge with other hosts, beginning with Eddie Brock, its second and most infamous host, with whom it first became Venom. Originally a villain and one of Spider-Man's archenemies, Venom has since evolved into an antiheroic figure, slowly distancing himself from his initial goal to ruin Spider-Man's life to try and do good instead. After Brock, numerous other hosts for Venom followed; some of the most notable are the villain Mac Gargan, who was the main incarnation of Venom from 2005 to 2009, and Flash Thompson, who became the superhero Agent Venom in 2011.