Corn snakes look similar to the venomous copperhead snake and are often killed because of this similarity. Corn snakes are harmless and beneficial to humans. They are one of the most common snakes kept as pets, alongside the garter snake and ball python. Corn snakes lack venom and help control populations of wild rodent pests that damage crops and spread disease. They can be distinguished from copperheads by their brighter colors, slender build and lack of heat-sensing pits.