The purpose of a digital camera is to store pictures and video in electric format instead of to film. A camera that is always connected to a computer with no storage could also be technically referred to as a digital camera, although this is typically called a Webcam.
Digital cameras typically have an LCD screen that allows users to view photos and videos stored on the camera. Users can choose which pictures to save and/or print instead of developing the whole roll, which film cameras require. Digital cameras also have much more storage space than film cameras and are able to store hundreds and even thousands of pictures.