What is the difference between Uniswap and Uniswap v3?

Can you please clarify the key distinctions between Uniswap and its upgraded version, Uniswap v3? I'm curious to understand how the latter has improved upon the former, especially in terms of features, efficiency, and user experience. Are there any significant changes in the way traders interact with the platform, or has the underlying technology been significantly overhauled? Your insights would be invaluable in helping me grasp the nuances between these two popular decentralized exchange protocols.