2.2 Polkadot
Polkadot was founded to tackle key points of failure of the blockchain technology. It is a blockchain ecosystem consisting of parachains. The idea behind it is to connect different blockchain projects, allowing value and data to be sent across otherwise incompatible networks. Every project in the Polkadot ecosystem leverages its unique shared security system, called the Relay Chain.
The Relay Chain is Polkadot’s main network, offering security and interoperability between the different parachains. For more information on Polkadot, check their official documentation or their lightpaper.