Chris Patterson presented on event driven architecture. He introduced event driven architecture as a method where events flow between decoupled components and services. He defined events as representations of changes in state that are self-contained and identified. Events can be business events related to real world occurrences, lifecycle events for processes and states, or management events related to time and limits. The presentation discussed how events are published and consumed asynchronously between independent components using messaging systems like MassTransit. Commands were also introduced as messages telling components to perform actions.