Uniswap does not allow any central authority on most of the exchanges. It offers automatic liquidity by its open-source protocol. If any DeFi platform uses this protocol, then it can enjoy quick token exchanges at a lower rate.
Automatic liquidity facilitated by Uniswap enables trading options without the requirement of order books. Uniswap functions on the model where liquidity providers can create liquidity pools and offer it to Uniswap.
ERC20 tokens can be exchanged for ETH tokens on the DeFi platform. A decentralized pricing mechanism system manages the price value.
As the Uniswap protocol functions in a decentralized way, no liquidity pool is offered to the traders. The token's price value depends on the market price rather than the price set by the buyers/sellers.