One of the very first things you should do before writing a
line of application code is architect the application tier to maximize and
exploit the ASP.NET Cache feature.
You simply need to include a reference to System.Web.dll in
your application project. When you need access to the Cache, use the
HttpRuntime.Cache property (the same object is also accessible through Page.Cache
There are several rules for caching data. First, if data can
be used more than once, it is a good candidate for caching. Second, if data is
general rather than specific to a given request or user, it is a great
candidate for the cache.