It is generally accepted that social talks have nothing to do with on-task discussion, or even that they are to be discouraged in the interests of effective learning. However, from a community-building perspective, social interaction is key to the sustainability of a learning community. An apparent paradox seems to exist in that, while social interaction is critical for community cohesion, social postings do not contribute to effective discussion. The authors argue that previous research using postings as the unit of analysis has failed to discover the context in which effective learning took place. Using threads as the unit of analysis, this study is able to explore empirically the relationship between effective discussion and social talks in CSCL environment. Based on an analysis of 321 longer threads (consisting of 10490 postings) in which the structure of the threads, the components of the threads, and the order of different categories of postings in some of these threads were defined, this study reveals that genuine effective discussions and social talks cannot be viewed in isolation nor does there exist a wall between them. The roles of social talks in CSCL are rediscovered and discussed.