Balancer (BAL) is an Ethereum token (ERC-20) that powers the Balancer protocol, an Automated Market Maker (AMM) that lets anyone create or add liquidity to trading pools while earning customizable trading fees. Balancer innovates on top of traditional AMMs by allowing more than two assets to be added to any liquidity pool. This creates a structure where anyone can create an index fund with specific weights on each asset and the Balancer protocol will automatically adjust the fund’s positions. At the same time, users can trade assets with the liquidity pool without going to a middleman. This makes Balancer a fee-earning index fund for liquidity providers as opposed to fee-charging index funds in traditional finance. 

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