Activity Theory is a framework that describes the unity of activity and consciousness. It emphasizes that consciousness does not include cognitive acts but is related to daily practice. The theory proposes a robust notion of mediation, where humans experience and structure their experiences through sign systems and tools. Activity Theory also focuses on the significance of consciousness and motives, which are essential for every human being. The theory has been applied in various domains, including information systems, organizational change, and IT system deployment. It has also been used to analyze work activities, design solutions, and develop techniques for both quantitative and qualitative approaches.