UNI is the Governance Token for Uniswap Platform. The holder has the right to determine the future of Uniswap by voting or commenting on the referendum.
400 UNI tokens were distributed to the users of Uniswap via an airdrop on 17th September 2020. The total value of the first batch was around $1,500. The users can farm for more UNI token by staking other tokens to the platform to help support the liquidity.