Physical theatre is a general term used to describe any mode of performance that pursues storytelling through primarily physical means. There are several quite distinct traditions of performance...
The reason for using Physical Theatre is Drama is basically because it adds more of a twist to the story and makes it more effective. Without this the audience watching wouldn't be as more intriged...
Physical theatre is a form of acting that tells a story through the way bodies are positioned and the way they move forming different shapes and places.