The purpose of this study was to explore how technology affects the social and cognitive dimensions of online learning. Using content analysis, open-ended questions and Anderson & Archer?s Community of Inquiry as a framework, cognitive, social, and teaching presence were analyzed in text-based discussion forum. Results revealed learners? ability, interest in the topic, and relation to the message sender affected their inquired, exchanged, and guided interaction patterns. The findings suggest that the instructor should arrange events irregularly for underpinning familiarity and commonality, and the learners should learn how to leave their learning trajectory in text-based environment.