How the Google Rich Snippets extension changes the source code of a website?

How the Google Rich Snippets extension changes the source code of a website?

The Google Rich Snippets extension adds a special Schema.org markup. You can find it on your pages in the source code (use the following keyboard shortcut to view the source code: Ctrl + U), for example:

     
      
You can also check the rich data using the Google testing toolIf Google doesn't detect any rich data on the home page, it means that it does not contain elements that can be displayed in snippets. Please note that the rich data is mainly intended for product and category pages. If you'd like to check it, please test some of your product pages. In case the rich data is correct, the testing tool will show results like this: