# Application (/en/docs/developers/application)



An application publishes a site (static files, Worker code, or both) to the platform and gives it a reachable address. Every publish creates a version, and a deployed version becomes the live one.

## Where to store data [#where-to-store-data]

Use the application's own `d1`, `kv` or `r2` components for runtime data such as orders and sessions, with business rules enforced by application code. Use Database for structured content, File for files and Knowledge for searchable knowledge: these are shared content stores that applications can read through public APIs, not their private runtime storage.

* [Runtime capabilities](/en/docs/developers/application/runtime-capabilities): what an application can and cannot do, and its limits.