Parachain
An independent blockchain connected to and secured by a central relay chain, letting it process its own transactions while sharing the relay chain's overall security.
A parachain is an independent blockchain that connects to, and derives its security from, a central relay chain (see Kaavon's "Relay Chain" glossary definition), an architecture popularized by Polkadot. Each parachain can have its own specialized rules, token economics, and governance, while relying on the relay chain's shared validator set to provide consensus security, rather than needing to independently bootstrap its own security from scratch the way a standalone Layer 1 blockchain would.
This architecture lets many specialized, purpose-built chains coexist and interoperate while sharing a common security foundation, conceptually similar in goal to how shared security (see Kaavon's "Shared Security" glossary definition) models let newer chains borrow established economic security rather than building their own from zero. A parachain typically needs to win and maintain a slot connecting it to the relay chain, with the specific mechanism for allocating those limited slots varying by implementation.
Examples
- A parachain specialized for a specific use case, such as decentralized finance or gaming, can rely on its relay chain's shared validator set for security rather than bootstrapping its own independent consensus.
- A parachain architecture lets many specialized chains coexist and interoperate while sharing a common underlying security foundation, rather than each needing to independently secure itself.