1. A method for identifying a user, comprising: identifying at least three contact regions on a touch sensitive surface, the contact regions defined by simultaneous contact of at least three fingers of the user with the touch sensitive surface; for each contact region, determining a center point; determining distances between each of the determined center points of the contact regions; comparing the determined distances against predefined distances associated with a known user, wherein comparing the determined distances against the predefined distances includes determining a sum of squared differences between each of the determined distances and a corresponding one of the predefined distances; based on the comparing, determining the user to be the known user or not the known user; wherein comparing the determined distances against the predefined distances includes determining whether the sum of squared differences is less than a maximum allowable error, wherein the user is determined to be the known user if the sum of squared differences is less than the maximum allowable error, and wherein the user is determined to be not the known user if the sum of squared differences is greater than the maximum allowable error; wherein the method is executed by a processor.