What is these two terms refers? According to me google will follow no follow link but don,t pass page rank as well as index the content.
No follow will not help much in PR but still could help in indexing and getting traffic to your website which is also considered by google for PR.
I would prefer dofollow because search engines recognize it while nofollow is still best when it comes to traffic for your website...
Two sides to this 'problem' One if you are looking for links from another site: dofollow passes link juice but nofollow is still a link and may send you traffic. Dofollow links using keywords you are targetting as anchor text are best of all. Other side is what you allow from your site? dofollow sucks away a bit of your link juice - but lots of people want to find these sort of links = more relevant activity to your site providing a higher ranking
Do follow and no follow are both good. At least for traffic. But in both cases it should be a link on a relevant site. (relevant to your niche that is.) For Serp only do follow counts.
Do follow and No Follow both helps to get traffic but no follow doesn't help to get page rank You could not get any back links from no follow websites. Do follow always better than No follow websites.
Some people insist that nofollow links pass a tiny bit of juice and that in bulk they can help your ranking. I don't personally believe that's true, but if it is, dofollow links are worth so much more it's not even worth it to think about the nofollow ones.
When you make a link no follow by adding rel="external nofollow" , it simply tells the spiders not to crawl that particular link .no follow links are not counted as backlinks and vice-versa for do follow links. In do follow links you loose some link juice. There are advantages and disadvantages of both no follow and do follow Some advantages of do follow are you get lots of comments and people frequently comment in-order to get backlinks, but on the other hand you get a lot of spam comments like "great" "cool" etc the only motive is to get link to their site. and vice-versa for no follow.check how to make links no follow and some advantages and disadvantages discussed.
Weird thing is some of the nofollow links are considered and counted as backlinks, no kidding. So I begin to think nofollow attribute doesn't matter. You can go to yahoo site explorer to check a site's backlinks