Polkadot (cryptocurrency)

The polkadot chain is at the center of the polkdadot architecture providing the relay chain between a variety of parachains and virtual parachains (e.g. EthereumEthereum, Zcash, etc). Scalability would come from parallelizing problems across multiple parachains. The relay chain coordinates consensus as well as the passing of any generic type of message between the chains. Messages are generic and can represent hashed bundles of transactions or any other arbitrary data. Thus the relay chain adds no functionality or complexity beyond pooling consensus and security across the chains and passing messages.