Polkadot is a platform that allows diverse blockchains to transfer messages, including value, in a trust-free fashion; sharing their unique features while pooling their security. In brief, Polkadot is a scalable, heterogeneous, multi-chain technology.

Polkadot is heterogeneous because it is entirely flexible and makes no assumptions about the nature or structure of the chains in the network. Even non-blockchain systems or data structures can become parachains if they fulfill a set of criteria.

Polkadot may be considered equivalent to a set of independent chains (e.g. a set containing Ethereum, Ethereum Classic, Namecoin and Bitcoin) except with important additions: pooled security and trust-free interchain transactability.

Unlike previous blockchain implementations that provide a single chain of varying degrees of generality, Polkadot provides a Relay Chain upon which a large number of verifiable data structures may be hosted. We call these data-structures “parallelized” chains or parachains. Polkadot provides a networking and consensus layer that allows blockchain developers to focus on creating a state machine with unique features, such as formal verification or anonymity.

Polkadot consists of many parachains with potentially differing characteristics. Transactions can be spread out across the chains, allowing many more transactions to be processed in the same period of time. Polkadot ensures that the security of all blockchains in the network is robust and that any dealings between them are faithfully executed. All parachains share security and state, meaning if one chain has a message reverted, all chains get reverted. It is also possible for independent chains with their own validators to be linked to Polkadot via bridges, thereby foregoing Polkadot’s shared state and security system. These chains can benefit from Polkadot’s interoperability without being hosted on the platform, examples of these would be Bitcoin and Ethereum.