The computer-services and software industry used to be conveniently divided into three main sectors: mass-market software vendors, enterprise software vendors, and computer services. The three sectors were distinct, because personal computers, corporate mainframes, and online computer networks...

This article reviews the changes to the established software industry caused by the rise of the Internet. Before the advent of the commercial Internet (in 1994, say), the industry consisted of three distinct sectors: vendors of mass-market software products for PCs; vendors of enterprise...