Looking at a snake, you might think that it has no bones. It seems to squeeze its way through the tiniest of cracks in the ground or on the trees. But the truth is that a snake has more bones in it back than any other animal. This bones, called vertebrae, are linked to one another by thousands of muscles. The snake can move these muscles to crawl in various way-sideways, winding to and fro and moving in big loops.
Some snakes do not have teeth at all, while other have very sharp ones. They do not use these teeth to tear or chew their food. They use them for gripping their prey, which they swallow whole. Poisonous snake have a pair of sharp and long teeth, called fang, with which they inject poison in to their prey.
Source: https://www.youtube.com/watch?v=oOdSwkFfOWs
