This paper analyzes the impact of a variety of socio-economic, demographic and regional factors to explain Internet use and the frequency of use by individuals in Spain. We have employed binomial and ordered probit models with a Heckman's two-stage estimation procedure. This allows us to distinguish between different variables and explain both use and the intensity of use, respectively. Internet use is mainly associated with education, age, occupation, employment in service sector, nationality, urban areas and regional GDP per capita. In contrast, frequency of Internet usage is positively related to broadband connection, education, Internet skills, the ways through which Internet skills are acquired, gender, and population size. Knowledge of differences in the determinants of Internet use and its extent of use may help to specify the most suitable policies for each case.