What is the difference between Uniswap and Uniswap V2?

Excuse me, could you please elaborate on the key differences between Uniswap and Uniswap V2? I understand that both are decentralized exchanges on the Ethereum blockchain, but I'm curious about the specific upgrades and changes introduced in Uniswap V2. For instance, are there any improvements in terms of efficiency, liquidity, or user experience? Additionally, how do these changes impact traders and liquidity providers on the platform? I'd appreciate your insights into these aspects.