Transaction Logic (TR) is an extension of classical logic that accounts for the phenomenon of state changes in knowledge bases. It allows specification of static and dynamic constraints, nested transactions, triggers, etc.
Viewing a Web site application as a knowledge base and given the linear feature of such applications (sequence of states changing over time), makes TR a suitable modeling tool for such task. In this presentation, the main concepts of TR will be briefly presented followed by a discussion on how to specify web site applications using TR.