what is Http handler?and how its work??

Hi,

An ASP.NET HttpHandler is a class that implements the System.Web.IHttpHandler interface.

Any class that implements the IHttpHandler interface can act as a target for the incoming HTTP requests.It is a process 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.

Please go through below links for more details -

https://msdn.microsoft.com/en-us/library/ms227675(v=vs.100).aspx

http://stackoverflow.com/questions/391130/what-is-an-httphandler-in-asp-net