So far, the temporal order of clicks has been taken to be equal to the structural order of a session. With the advent of the newest browser generation where the use of multiple tabs has become a common feature, the above assumption does not necessarily hold any more. It is crucial to understand how the use of multiple tabs impacts on web usage mining, especially on the understanding of a session and its reconstruction.

In order to analyze this new browsing behavior, we introduce a generic browsing model extending the traditional serial or single window model to cover the use of multiple tabs. Based on this model, we present and analyze an approach to detect use of multiple tabs within sessions. The existence and increasing prominence of the use of multiple tabs is shown by this approach to be of relevance to business analysis as well as research results.