The Internet is a new information channel that has given rise to a wide variety of new services. It is quite challenging to analyse the economic impact of this multifaceted and changing set of activities, since Internet-related services blur traditional boundaries, particularly those between market activity and volunteer and informal activity. The goal of this study therefore remains modest: to draw up a typology of the main activities that could not have emerged without the Internet; explain how they are traced in the national accounts, which are the frame of reference used to describe the economy; and describe themain findings of economic research into the Internet's impact on business volume, price, and well-being. The analyses presented in this document will obviously need to be supplemented by further studies to evaluate progress in economic research and new categories of services that will surely emerge in the coming years.