In a perfect world you aim for everything to be cached, except the actual page content to minimize the download time and speed up a visitors user experience.
Some caching might take place on the server, or by the browser but ideally you want to end up with a picture that looks somewhat like this:
And while you can control the caching of the page content itself from within Sitefinity
(page>properties) there is no built in method to control static content like javascript, css or images.
In order to achieve this optimum setup, we need to turn to our web.config ...