Social networking sites such as Twitter, Facebook and My Space have experience rapid worldwide growth. It is crucial that this global phenomenon be investigated within the South African context. Social networking is a relatively new trend in South Africa and there is a paucity of academic literature on the topic. This quantitative study investigated one of the most popular social networking websites to date, namely Facebook. Facebook is a social networking website which was launched in early 2004. The primary research question focused on determining the usage patterns of South African Facebook users. In specific, the study investigated the purposes for which the site was used, the self-reported substitution of Facebook usage for face-to-face interaction and the relationship between Facebook affinity and Facebook use. A survey research design was used to collect data via an electronic questionnaire posted on Facebook. The theoretical point of departure was post-positivist. Media theories applied to the phenomenon under investigation include the uses and gratifications theory and the theory of the niche. The findings suggest that Facebook is primarily used for its intended purpose of communication. The respondents reported the gratification of versatile (multipurpose) communication. Furthermore, only half of the sample reported privacy concerns regarding Facebook. There was no significant indication that Facebook is a substitute for face-to-face interaction. Half of the sample claimed that their interpersonal contact has increased as a result of Facebook use. In addition, in accordance with expectations, the more affiliated a person is to Facebook, the more they will use Facebook. The findings of this study conform to other studies concerning social networking and provide a South African view of the global phenomenon of social networking websites.