Is the theory of plate techtonics and continental drift the same?

Continental drift theory was proposed before the discovery of the mid-oceanic ridge, when it was hypothesized that the continents were actually plowing through the oceans. This theory was an attempt to explain the commonality of fossils on opposite sides of the Atlantic Ocean, and the observation on maps of the Earth that the North American and South American continents appeared to have been pulled apart from Europe and Africa. With the discovery of the mid-oceanic ridge, where new crustal plate is being created, and subduction zones, where plates are being destroyed, plate tectonic theory was born; that the crust of the earth is divided into many segments that are in constant motion, that the oceanic crust is constantly being recycled--all driven by heat from the Earth's interior. Plate tectonics is now nearly universally accepted as scientific fact, yet questions remain to be answered on some of the mechanisms of the process.