Figure 10.1: Architecture of Polkadot

(Source: https://wiki.polkadot.network/docs/getting-started)

Relaychain

It’s the main Blockchain that plays a central hub in Polkadot’s

ecosystem. The Relaychain has all the validator nodes staked on its

network. The Relaychain’s main task is to handle and coordinate the

entire network of Blockchains together. It does not support smart

contracts.

Parachains

These are different parallel Blockchains that can work independently

on top of the main relaychain. The Relaychain has many different

slots for Parachains to occupy and stay connected with the

Relaychain for a particular time period.