xDai Chain is a USD stablecoin blockchain jointly launched by MakerDAO Foundation and POA Network. It is also a side Chain compatible with Ethereum. It uses stablecoin xDai (converted 1:1 on the side chain by decentralized stablecoin Dai on Ethereum) as the base token for transactions and gas payments, and uses STAKE token for accounting and governance with the help of a unique proof-of-stake algorithm, POSDAO.

xDai Chain adopts the mode of single token for transaction and payment of gas, which eliminates the trouble of having to hold extra ETH to pay gas on the ethereum main network, and can realize low-cost fast payment and stable handling fee. It is very suitable for building application scenarios based on payment and DeFi. In the future, this side chain model will be further extended to staboins other than Dai and other main chains other than Ethereum, with STAKE remaining as the governance token for these side chains.