The primary differences between classic Google Sites and the new Google Sites lie in their design, usability, and feature set. Classic Google Sites, introduced in 2008, offered a more traditional web-building experience with an extensive range of customization options through HTML and various embedded gadgets. It was more flexible in terms of layout control and allowed for detailed structural customization, but it often required more technical knowledge to achieve desired results.

In contrast, the new Google Sites, launched in 2016, focuses on ease of use and modern design. It provides a more intuitive, drag-and-drop interface, making it accessible even to users with no web design experience. The new version emphasizes simplicity and streamlined functionality, allowing users to create visually appealing, responsive websites that automatically adjust to different screen sizes without needing manual adjustments. This makes the new Google Sites particularly user-friendly and ideal for quickly creating professional-looking websites.

Another significant difference is in integration and collaboration features. The new Google Sites integrates more seamlessly with other Google Workspace apps, such as Google Drive, Google Docs, and Google Calendar, enhancing the ability to embed and collaborate on content. It also offers better support for team collaboration, with real-time co-editing capabilities similar to those in Google Docs and Sheets.

While the new Google Sites is easier to use and offers a more modern approach to web design, it lacks some of the advanced customization options available in classic Google Sites. Users who need detailed control over their site's structure and design may find the new version somewhat limiting. However, for most users, the improved usability, responsive design, and enhanced integration with Google Workspace make the new Google Sites a superior choice for creating and managing websites.

For further details on the differences and migration process, you can refer to the Google Sites Help Center and various guides on transitioning from classic to new Google Sites.