DudaOne sites are not only responsive to different screen sizes, but also automatically detect the type of device that's being used to access the website (desktop, tablet, or mobile). DudaOne will then display custom content and features specific to that device. This process is called "dynamic serving," and Duda automatically adds a custom HTTP header to inform search engines that the content will vary by device.
To follow SEO best practices, Duda automatically implements the vary http header for your site. This is not visible to any user, but notifies search engines that we are delivering different content to different device types. This way the search engines can correctly index your website.
The vary http header would look something like this to a browser or search engine:
HTTP/1.1 200 OK Content-Type: text/html Vary: User-Agent Content-Length: 5710 (... rest of HTTP response headers)
This communicates that the website varies by user-agent (a technical term for browser type). No action is required on the user's part to implement the vary header, DudaOne takes care of it for you automatically.