How Google Diffrentiate
 

Hello I want to know that, I have two website, content of website are same then how Google will differentiate b/w them to give popularity..

Its not a good for seo perspective to optimize to website with similar contents , you are awaiting for penalty.

The date of the cache of the pages and date of publishing of the site will be considered by Google is identifying duplicate and original content sites.

google saves the content of the page in the index in the form of keywords.