This is very simple question but its answer will be very useful from SEO point of view. In Google, you'll find two options

when searching - "the web" and "pages from country" (for example pages from Canada, pages from India etc).

So could anyone please tell me that what is the technical difference between these two option and how it effects any search?

Basically the region and the language of the website, webmasters are having the ability to set up their language or targeted country at Google webmaster.