Web Forms is one of four programming models in Microsoft’s .NET web application framework. With the introduction of Web Forms in 2002, Microsoft allowed developers to manage website state and form data across pages, and provided the ability to add C# or VB code behind web page objects. Web Forms also contained a large number of server-side controls.
However, there are some disadvantages to Web Forms. Unlike other models like MVC, Web Forms does not force a standardized architecture on an application. Business-level code can be placed on objects themselves, instead of in a separate business object, reducing reusability. Testing controls in Web Forms is difficult as well. Nonetheless, Web Forms allowed programmers to quickly create web applications by using the controls and events model familiar to them from Windows applications.