What is Google Cache?

Google takes a snapshot of your web page while crawling through your web pages and stores as a back up. So we can say, that Google even backs up your data and can be used to get back some important data if you have lost. For example, you lose all your data from your server and you want to see a page, you just need to do the following

Go to Google.Com

In the search box, just type site:yourdomain.tdl

You will get all your indexed pages listed. Go to the page that you need and click on the cache link which you will find under the snippet on the search result page of Google

You will be able to see your page as its stored on the Google Sever.

Can you imaging the number of pages that Google has stored on its server?