Output caching
Output caching lets you cache entire pages or sections of pages on the server itself. It gives you the following advantages:
Flexibility: Supports caching different versions of files, by query string variable, request header, or a custom variable.
Allows caching of parts of a page.
Life span of cached items is relatively predictable no competition for cache space by other websites. This may not apply if you use shared hosting, where many websites use the same web server.
It comes with the following disadvantages as well:
Not really suitable for caching visitor-specific pages because this would mean storing many pages with low hit rates.
Uses server memory.
No caching across servers because the cache is all in server memory. In a web farm, each server has its own cache. This means that each file is duplicated over multiple web servers' caches, taking more memory than needed and leading to possible inconsistencies between the versions in each cache.
If the application pool recycles...
