Is the Internet a superhighway to information or a high-tech extension of the home telephone? We address this question by operationalizing information acquisition and entertainment as the use of the World Wide Web and interpersonal communication as the use of electronic mail (e-mail), and examine how 229 members of 110 households used these services during their first year on the Internet. The results show that e-mail drives people's use of the Internet. Participants used e-mail in more Internet sessions and more consistently than they used the World Wide Web, and they used e-mail first in sessions where they used both. Participants used the Internet more after they had used e-mail heavily, but they used the Internet less after they had used the Web heavily. While participants' use of both e-mail and the Web declined with time, the decline in Web use was steeper. Those who used e-mail more than they used the Web were also more likely to continue using the Internet over the course of a year. Our findings have implications for engineering and policies for the Internet and, more generally, for studies of the social impact of new technology.