Http Handler vs Http Module

• What is ASP .Net  HTTP Handler

An ASP.NET HTTP handler is the process (frequently referred to as the "endpoint") that runs in response to a request made to an ASP.NET Web application. The most common handler is an ASP.NET page handler that processes .aspx files. When users request an .aspx file, the request is processed by the page through the page handler. You can create your own HTTP handlers that render custom output to the browser

Reference: http://msdn.microsoft.com/en-us/library/bb398986.aspx

• What is ASP.Net HTTP Module

An HTTP module is an assembly that is called on every request that is made to your application. HTTP modules are called as part of the ASP.NET request pipeline and have access to life-cycle events throughout the request. HTTP modules let you examine incoming and outgoing requests and take action based on the request.

Reference: http://msdn.microsoft.com/en-us/library/bb398986.aspx

Note:   The basic different between HTTP Handler and HTTP Module, is that HTTP Module is event based processor.

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