Rococo is a testnet runtime with no stability guarantees.
The [Cumulus Tutorial](https://docs.substrate.io/tutorials/v3/cumulus/start-relay/) details building, starting, and
testing `rococo-local` and parachains connecting to it.
The [parachain registration process](https://docs.substrate.io/tutorials/v3/cumulus/rococo/) on the public Rococo
testnet is also outlined.