In addition to providing police new tools for enforcing the law, computers also raise numerous problems for both defining and preventing crimes. Consider the question of how the law should classify a "computer break-in"–which consists, not of anyone actually breaking into anything, but of one computer sending messages to another and getting messages in reply. Or consider the potential for applying the classical salami technique–stealing a very small amount of money from each of a very large number of people–in a world where tens of millions of people linked to the internet have software on their computers designed to pay bills online.