Who: Polygon (formerly Matic Network), Founders Jaynti Kanani, Sandeep Nailwal, and Anurag Arjun, 81 employees
What: Multichain scaling solution for Ethereum, using Layer 2 sidechains (PoS chain and Plasma chain). Users can deposit Ethereum tokens to a Polygon bridge smart contract, interact with them within the Polygon sidechain, and then later withdraw them back to the Ethereum main chain. Some developers consider it a “commit” chain that features Tendermint type PoS and 2-phase commits (see video below).
When: Founded 2017, mainnet live May 2020, rebranded to Polygon February 2021
Why: Matic expanded its scope and launched Polygon, the first well-structured, easy to use platform for Ethereum scaling and infrastructure development. Core component is Polygon SDK, a modular, flexible framework that supports building and connecting secured chains (aka layer2 chains) and stand-alone chains (sidechains).
How: $5M private sale and launchpad sale, now listed on Coinbase and valued at almost $4B
Strengths: Live layer 2 solution with long list of clients (Aave, Curve, etc.). Unlike other Plasma solutions, transfer from L2 back to L1 only takes about 15 minutes.
Weaknesses: Matic Token (needed to pay gas fees on the network) have a very volatile price
Future Plans: ZK Rollups and Optimistic rollups, standalone chains, shared security chains
Polygon Litepaper - https://polygon.technology/lightpaper-polygon.pdf
Polygon PoS Chain - A Commit Chain? DeFi Explained video - https://www.youtube.com/watch?v=f7F67ZP9fsE