Many groupware systems now allow people to converse and casually interact through their computers in quite rich ways—through text, images, video, artifact sharing and so on. If these interactions are logged, we can offer these multimedia histories to a person in a manner that makes them easy to review. This is potentially beneficial for group members wishing to find and reflect on their past interactions, and for researchers investigating the nuances of online communities. Yet because we have little knowledge of what people would actually do with these histories, designing an effective history review system is difficult. Consequently, we conducted a user study, where people explored real data from an online community. Our study identified a set of tasks that people would do if they could review these histories of casual interaction. It also produced a list of parameters pertinent to how we could visualize these historical records in a tool. With the increasing popularity of computer...