[[introduction]]
= Introduction

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When the framework renders a domain object, and as the end-user interacts with the domain object, the framework it emits multiple events using the intra-process xref:refguide:applib:index/services/eventbus/EventBusService.adoc[event bus].
These events enable other domain services (possibly in other modules) to influence how the domain object is rendered, or to perform side-effects or even veto an action invocation.

The framework has several categories of events: domain events, UI events and lifecycle events.
Learn more about these in xref:events.adoc[events] page.

To receive the events, the domain service should subscribe to the xref:refguide:applib:index/services/eventbus/EventBusService.adoc[EventBusService], and implement an appropriately annotated method to receive the events.


