What is the difference between point and shoot camera and DSLR camera?

A single lens reflex (SLR) is a camera that uses the same set of lenses to both focus the image on the CCD (digital) and enable the photographer to frame the picture. That is to say, when you look through the viewfinder of a DSLR you are looking directly at the object through the main lens. You are not looking at the digitally re-created picture of the object or through some other lens that is off-center of the main lens.

A point-and-shoot camera will have some other mechanism for framing the picture.