Ribbon Snake pictures (Thamnophis sauritus).
The Ribbon Snake's name (as shown in these pictures) comes from the shape and motion of it's body: they're long and slender. That body shape allows them to move and strike quickly.
Ribbon snakes are closely related to garter snakes. Both species are "live-bearers", giving birth to batches of live snakes instead of laying eggs. Like all reptiles, they still generate eggs within they're body; essentially the eggs hatch inside the body and the shells are absorbed by the mother.