The Key difference between Web2 & Web3 are
1. Tech Stack
Technologies used in Web 2.0 are HTML5, CSS3, AJAX, and JS. Web3 Technologies used in Web3 are ML, AI, and decentralized protocols.
2. Web 2 places more emphasis on contact and community building. on other hand, Web3 concentrated on decentralization, boosting individual users, and semantic learning.
3. Every Payment platform or App in Web 2 requires personal data & information for transactions. Web3 payment apps do not request personal information and cannot even stop payments.
4. Web apps in the current generation. Artificial intelligence (AI), and Machine learning-based smart apps.
5. The network owns the data. Web3 allows users to own data and have the right to use and share it.
Those are just a starting explanation of the differences between Web2 & Web3. You can know more about the Web3 here: https://www.bitdeal.net/web-3-0-development-company