What is effect of no follow or Do follow links ?

What is effect of no follow links and Do follow for ranking of a site under a particular keyword ?


Do these no follow links are effective for ranking or not ?

No-follow' links doesn't have any impact in rank position on search engine's result page, because they are not followed by search engine. The only purpose of creating no-follow backlinks is to get more traffic to a website.

Do-follow links is very effected compare to No-follow links

Dofollow links will be crawled by search engines and will be calculated as a backlink for the website.
Nofollow links will not be crawled by search engines but can help to boost the traffic to the website.