Lizards are a large, diverse group of reptiles. Around 3800 species live on land and in sea, on every continent except Antarctica. They range in size from geckos and chameleons (as small as a few centimeters) to komodo dragons (nearly three meters). Their used to be mosasaurs, which reached 17 meters! They proved to be too large and dangerous for Noah and his crew and so, went extinct.
The "once" mighty mosasaur
Although lizards give a lot of people the willies, most pose no threat. Gila Monsters and Beaded Lizards are poisonous but not likely to kill you, just give you a lot of pain. Komodo Dragons, on the other hand, are nothing to mess with. They sometimes stalk and attack humans and as recently as 2007, one killed an Indonesian kid. Nonetheless, in 2001, Sharon Stone's idiot husband bribed a zookeeper to let him see one up close and ended up in the hospital as a result. She divorced him three years later.
Please don't feed the dragon -- your toe
Numerous less dangerous species of lizard are kept as pets. Their owners often walk around with them on their shoulders and are the types to have weird goatees and other features designed to hammer home their eccentricity. Don't be one of those people.