Also known as variable-information printing, variable data printing allows elements such as text, graphics and images to be altered from one printed piece to the next, without stopping or slowing down the printing process and using information from a database or external file. Think of creating a set of personalized letters, each with the same basic layout, and printing them with a different name and address on each individual letter. This can be used for direct marketing, advertising, invoicing or putting addresses on self mailers, brochures or postcard campaigns.