A Web Form consists of two parts:
The visual content or presentation, typically specified by HTML elements.
Code that contains the logic for interacting with the visual elements.
A Web Form is physically expressed by a file with the extension .aspx. Any HTML page could be renamed to have this extension and could be accessed using the new extension with identical results to the original. Thus Web Forms are upwardly compatible with HTML pages.
The way code can be separated from the form is what makes a Web Form special. This code can be either in a separate file (having an extension corresponding to a .NET language, such as .vb for VB.NET) or in the .aspx file, within a <SCRIPT RUNAT=“SERVER”> … /SCRIPT> block. When your page ...