Polkadot is an open-source sharded multichain protocol that connects and secures a network of specialized blockchains, facilitating cross-chain transfer of any data or asset types, not just tokens, thereby allowing blockchains to be interoperable with each other. Polkadot was designed to provide a foundation for a decentralized internet of blockchains, also known as Web3.

Polkadot is known as a layer-0 metaprotocol because it underlies and describes a format for a network of layer 1 blockchains known as parachains (parallel chains). As a metaprotocol, Polkadot is also capable of autonomously and forklessly updating its own codebase via on-chain governance according to the will of its token holder community.

Polkadot provides a foundation to support a decentralized web, controlled by its users, and to simplify the creation of new applications, institutions and services.

The Polkadot protocol can connect public and private chains, permissionless networks, oracles and future technologies, allowing these independent blockchains to trustlessly share information and transactions through the Polkadot Relay Chain (explained further down).

Polkadot’s native DOT token serves three clear purposes: staking for operations and security, facilitating network governance, and bonding tokens to connect parachains .

Polkadot has four core components:

Relay Chain: Polkadot’s “heart,” helping to create consensus, interoperability and shared security across the network of different chains;
Parachains: independent chains that can have their own tokens and be optimized for specific use cases;
Parathreads: similar to parachains but with flexible connectivity based on an economical pay-as-you-go model;
Bridges: allow parachains and parathreads to connect and communicate with external blockchains like Ethereum.