> [!abstract] A specification for describing event data in a common way, providing a consistent schema for events across systems.
## Key Properties
- **data** - the actual event payload (custom per event type)
- **id** - unique identifier generated at publish time (enables idempotency)
- **source** - where the event came from
- **type** - the event type with version number (e.g., `order.confirmed.v1`)
- **traceparent / tracestate** - for distributed tracing (OpenTelemetry)
## Benefits
- Consistent schema across all events
- Built-in support for [[Event Versioning]]
- Enables idempotency checking by consumers
- Supports distributed tracing
## Sources
[CloudEvents Specification](https://cloudevents.io/)
[[x_Sources/Videos/Video - Build An Event Driven System - NDC Oslo 2024|Build An Event Driven System - James Eastham (NDC Oslo 2024)]]