To gain access to the network's proof-of-stake transaction validation and security, blockchains can connect to Polkadot and operate in parallel as "parachains." The network's "relay chain" verifies transaction addresses and standardises data so that all systems can understand it. This is the location where all of the chains' security is centralised.

While functionality is handled, Polkadot-connected blockchains are free to use their own PoS method, choose when and how to upgrade their code, and run any apps or tokens they want. It is a selectable layer that allows networks to maintain security while incorporating new protocols.

Polkadot is a next-generation blockchain platform designed to enable interoperability between multiple blockchains. It operates using a central Relay Chain, which coordinates security and consensus, and multiple connected parachains (parallel blockchains) that process transactions in parallel for scalability. Polkadot uses a Nominated Proof-of-Stake (NPoS) consensus mechanism, where validators secure the network, nominators stake DOT tokens to support validators, and collators gather data for parachains. Its cross-chain messaging system (XCMP) allows parachains to exchange data and assets seamlessly. Polkadot also supports on-chain governance, enabling token holders to vote on upgrades and proposals. By facilitating a decentralised, scalable, and interconnected blockchain ecosystem, Polkadot aims to solve issues like slow transactions, high fees, and isolated networks seen in older blockchains.