Mola is a genus of two species (Mola mola and Mola ramsayi) in the family Molidae, the ocean sunfish. Mola mola is the most common of the ocean sunfish and gave the Molidae their English common name from its habit of "sunbathing" at the ocean surface. Molidae is one of the most recently evolved groups of fishes, descending from reef fish just 40 million years ago and is in the order Tetraodontiformes, which includes puffers and porcupine fish.

Mola grow to be large, with an average size of 1.8m (6ft) and a record size of 3.1m (10ft). They have rough and leathery skin covered with a thick coat of mucus. Their coloration ranges from silvery-gray through spotted to white and they are capable of sudden changes in color in response to unexpected stress, such as predator attacks. Their life span remains unknown.

Mola have a diverse diet and are known to feed at multiple levels in the water column, but they focus on gelatinous floating prey like jellyfish. Mola are infamous for the high count and numerous types of parasites that can be found on any single individual. Their large size allows them some security from predators, but they suffer large losses as bycatch in human fisheries.