Caching with web content is a great way to reduce your bandwidth bills and server strain. Karin Huber has written an article on different methods on how to get ASP.Net and IIS to cache content on the client's computer.
Karin talks about how to get IIS to cache different files and folders but since you may not have access to IIS if you're in a shared environment, she then goes on to talk about how to do it in ASP.Net
By adding in a HttpHandler, one is able to process the request in ASP.Net. To do this, you create a new class that extends the IHttpHandler interface.