Using ASP.NET, you can create HTTP modules and HTTP Handlers at the same time with less code and frustrations. HTTP modules are components available in the HTTP request pipeline that interrupt the incoming ASP.NET requests. You can set up cookies, authentication verification, and other things using HTTP modules. HTTP handlers on the other hand, is the last place for incoming web requests. It processes the requests then send it back for response. With the introduction of tasks in ASP.NET 4.5 and async/await features, creating asynchronous HTTP module and HTTP handlers become much simpler than before.
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