HTTP Modules are another way of handling any request or any error by the user . It also helps us to handle wrong request and errors in a customized manner.

Add the following code to ASP.NET Module

public void Init(HttpApplication context)
{
    context.BeginRequest += new EventHandler(OnBeginRequest);
    context.EndRequest += new EventHandler(OnEndRequest);
}
void OnEndRequest(object sender, EventArgs e)
{
    HttpApplication appObject = (HttpApplication)sender;
    HttpContext contextObject = appObject.Context;
    // PageHeaderText is a constant string defined elsewhere
    contextObject.Response.Write("<table width='100%' border='2'><tr><td align='center' background='Gray'>The last event in the HTTP pipeline chain of execution</td></tr></table>");
}
void OnBeginRequest(object sender, EventArgs e)
{
    HttpApplication appObject = (HttpApplication)sender;
    HttpContext contextObject = appObject.Context;
    // Add custom header to the HTTP response
    contextObject.Response.AppendHeader("Author", "Himanshu Joshi");
    // PageHeaderText is a constant string defined elsewhere
    contextObject.Response.Write("<table width='100%' border='2'><tr><td align='center' background='Gray'>HTTP pipeline begins to process the
request</td></tr></table>");
}

And then add the httpmodule tag in Web.Config file

<system.web>
      <httpModules>
      <add name="MyFirstModule"
           type="Himanshu.SampleModule, SampleModuleAssembly"/>
    </httpModules>
</system.web>