The new tag filter feature in Bing Search is a tool that Microsoft is testing, which allows users to refine their search results based on specific tags. When using Bing Search, some users may see a tab on the right side of the page that, when clicked, expands to display various tag filter options. These options enable users to filter search results by entities such as Site or domain, Product/Service, Company/Organization, Event, Person, and Other.

To use the tag filter on Bing Search, you can click on the tab that appears on the right side of the search results page. This tab will expand to show you different tag filter options. You can then select the desired tags to filter your search results by specific entities like Site or domain, Product/Service, Company/Organization, Event, Person, or Other.

The new tag filter feature in Bing Search is somewhat similar to the existing Bing snippet tags, but it is described as being more interactive. While Bing snippet tags might provide additional context within the search results snippets, the tag filter feature allows for a more dynamic and user-driven way to refine search results by selecting specific tags that categorize the information.