Polygon, formerly known as Matic Network, is the first well-structured and easy-to-use platform designed to scale and develop Ethereum’s infrastructure. Its core component, the Polygon SDK, is a modular and flexible framework that supports building a wide range of applications. Polygon effectively transforms Ethereum into a mature multi-chain system, also known as the blockchain internet. This multi-chain system is similar to Polkadot, Cosmos, or Avalanche, but with the added advantages of Ethereum's security, active ecosystem, and openness. The $MATIC token continues to play an increasingly important role in securing the system and enabling governance.
Reference: CoinMarketCap