If you want the art to extend to the edge of the paper, the file you create for print will need to be set up to “bleed”. What this means is you will have an extra 1/8th of an inch added to the outside of the file. For example, if you are creating a 3.5″ x 2″ business card and you do not want a white border on it, you will need to create a file that is actually 3.75″ x 2.25″. You will extend the background artwork all the way to the edge, that way when the print is trimmed down to finish size (3.5″ x 2″) the artwork will extend all the way to the edge. Here is a graphic to help explain things….
In order to ensure there is no white at the edge of the business card, the art used is extended all the way to the edge of the 3.75″ x 2.5″ file. When the business cards are cut down to finish size, the art will extend all the way, leaving no white space. In addition, it is a best practice to keep all the content .125″ inward of the finish size. This is called the “safe area” or “safety margin” to ensure none of the content is accidentally cut off.