Méliès discovered many in-camera tricks like using multiple exposures, time lapse photography, dissolves, and substitution (having an actor stand in place, the camera is turned off, and object placed in the actors hands and the cameras turned on, giving the appearance of the object magically appearing on screen). Camera tricks have been around longer than most of us have been alive, yet even now we are still often fooled by them!
When Hurricane Irene moved through the Caribbean and East Coast of the United States the week of August 21 - 27, 2011, this picture started spreading all around the Internet:
This was a scene of a flooded street in Puerto Rico with a shark swimming through it. The picture was accompanied by the warning "...this is exactly why authorities in NYC are warning people not to go swimming in flood waters after a hurricane." While I had my suspicions about this picture, it certainly looked real. It was later revealed (via snopes.com) that this was a composite photo of a great white shark from another picture and the flooded street.
We all have the tendency to believe everything we see on the Internet as being real and true. But like Georges Méliès discovered, it's amazingly easy to fool people with a camera. These days we have applications like PhotoShop or the Gimp that can turn anyone into a bedroom Méliès.