They have moist, often slimy skin, with no scales, and with no claws on their toes. Amphibians hatch from shell-less eggs laid in water or moist places, and have a larval stage that usually differs structurally from the adult animal. Lizards are reptiles. They have dry skin covered with scales, and claws on their toes. They hatch from shelled eggs laid on land, or are born alive from eggs retained within the mother's body.
All reptiles breathe with lungs.
As they grow, their outer skin doesn't grow with them. Instead, a new skin grows underneath the old. When the old skin becomes too tight, the frog puffs itself up with air until the skin splits along the back. Warts in humans are caused by a viral infection and have no relationship whatsoever with toad warts. However, it's not a good idea to handle a toad.