What makes the Synthetix protocol so special is that it enables the creation of synthetic versions of cryptocurrencies and real-world assets (they have an ‘s' added to the ticker symbols) on Ethereum or Optimism networks. Synthetix also runs a decentralized exchange that offers trading functionality without having a registered account. Some of the most popular synths are sUSD, sEuro, and sApple. 
SNX is the native token of the Synthetix protocol used for staking and governance. Users of the network benefit from high yields earned through farming and staking up to 67% APY. SNX provides the backing for all the synthetic assets on the platform. To create synthetics, users need to stake SNX to mint a stablecoin sUSD against any collateral and redeem the synthetic asset. Furthermore, SNX is a governance token, meaning the holders have the ability to make recommendations for changes to the protocol and vote for suggestions made by others.