But i heard is few places that nofollow backlinks transfer a minuscule thing of pagerank to outward links but this ratio is real smaller than dofollow ones.
Nofollow links does not pass PR,but dofollow links pass PRNofollow are for not crawling a link by search engine. Dofollow allow search engine to crawl links. Nofollow tag we can use if we are using a link for reference not for crawl. Both are good for human traffic.