Well, a copyright shows ownership of an item. It shows that you are the original and true owner of that item. If someone uses that item without your permission this is infringement upon that copyright. A copyright infringement is really quite simple to prove once you have proven that you are the true and original owner of an item, be it a movie, and image, a song, a story, or any such item. Once this is proven the person or persons who violated that copyright are civilly liable for damages.
Civil liability is determined either by actual or statutory damages.
Actual damages would be what you have lost in a monetary amount by this person stealing your work. This amount can be determined by profits the person who stole the work gained by the theft of that item. The court, in what it feels the reasonable amount would be for the item that was infringed, determines this amount. In addition, any costs the person or person would have had to pay for the use of such an item can be added to the damages in the amount of two times the license fee for what should have been paid to the owner for use up to three years. In addition the person who infringed upon the copyright may be liable for all attorney fees amassed by the original artist.