Welcome to APUG and film photography.
Originally Posted by bellalee
As Patrick said, you must process the film before you can get any image. Film is light sensitive and any other exposure to light out of the camera will ruin anything in it.
When you expose the film in the camera, a latent image is formed on the emulsion (not visible). Processing does a chain of chemical reactions that convert that latent image to a visible image.
Well, Hybridphoto is the place for talking about scanning processes; but I guess there isn't anything wrong in answering your questions.
A scanner is just a sensor with a light that "captures" the reflected light and makes a file from it, paper is scanned this way. For scanning film, instead of reflected light, you need a backlight that illuminates the film.
There are Dedicated film scanners (Nikon, Minolta) and flatbeds with a transparency device (Epson V500/600/700).