Transactional Analysis (TA) is a theory that views personality as consisting of an internal Parent, Adult, and Child. Eric Berne discovered TA and proposed that people engage in ego states when interacting. Transactions are stimuli between people based on their current ego states. Straight transactions involve complementary ego states responding, while crossed transactions involve mismatched ego states. Berne also identified ulterior transactions, strokes, life scripts, existential positions, and games that people play for various psychological reasons. TA provides a framework for understanding interpersonal dynamics and improving communication.