The display modes in ASP.NET MVC and ASP.NET Web Forms is a way of separating a page from the content. It exists in ASP.NET MVC between the actions that follows request and generation of the subsequent response of the browser.
Web forms can be extended with convention-based tricks to automatically serve a different master pages in different browsers. This will also make server controls be capable of returning different values for different browsers. This is what makes Web Forms an advantage compared to older technologies.
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