All snakes are meat eaters but they have no limbs with which to hold down prey and no teeth with which to chew it. So, many snakes are armed with lethal poisonous fangs instead. These work rather like hypodermic needles. They inject poison into the prey and paralyze or kill it. This gives a snake the time to swallow it's quarry whole, safe from the danger of an active victim's sharp teeth or claws.