Caching can be a good way to get "good enough" performance without requiring a lot of time and analysis. Again, memory is cheap, so if you can get the performance you need by caching the output for 30 seconds instead of spending a day or a week trying to optimize your code or database, do the caching solution (assuming 30-second old data is ok) and move on. Caching is one of those things where 20% of the work provides 80% of the benefit, so it should be one of the first things you try to improve performance. Eventually, poor design will probably catch up to you, so of course you should try to design your applications correctly. But if you just need to get good enough performance today, caching can be an excellent, buying you time to refactor your application at a later date when you have the time to do so.

Please go thru the below MSDN Article.http://msdn.microsoft.com/en-us/library/aa478965.aspx