Polygon

Polygon is a scaling solution for public blockchains. Polygon PoS supports all the existing Ethereum tooling along with faster and cheaper transactions. Polygon is a sidechain. Think of a Sidechain as a clone of a 'parent' blockchain, supporting transfer of assets to and from the main chain. It is simply an alternate to parent chain that creates a new blockchain with its own mechanism of creating blocks (consensus mechanism). Connecting a sidechain to a parent chain involves setting up a method of moving assets between the chains.