What is google cache and what is the benifits of google cache..?

Google takes a snapshot of each page it examines and caches (stores) that version as a back-up. The cached version is what Google uses to judge if a page is a good match for your query. Practically every search result includes a Cached link.

Google Cache is a snapshot of a web page stored by Google. The cached copy is what Google uses to judge if a page is a good match for user's query.