No-follow links are not crawled so it has no much value for SEO. Do-follow is the best for seo and it will help you to get page rank and visitors also.
The "rel" tag defines any tag a "do-follow" or "no-dofollow" links. If you don't use rel tag, then Search Engines would consider every links as do-follow links. When we apply this tag rel="nofollow", this defines the following line to search engines:
That particular link won't pass the link juice and page-rank.
A nofollow link is a link that is included on a webpage using standard html markup but includes an attribute to prevent passing link juice or reputation to the destination page. This type of link does not improve the link target search engine ranking.
Here is a hyperlink to Google followed by the same link with the nofollow attribute added.
Google, Yahoo, and MSN all include nofollow links in site backlink counts. Google only shows a select few backlinks for each domain when using the link operator from the web interface. Google webmaster tools record of backlinks includes nofollow links even though they are absent using the link operator.
Interesting that in Google information for webmasters question number fourteen indicates that the nofollow attribute is a way to prevent Google from "crawling" an individual link on a page as well. This tells me that rel=nofollow does the following with Google:
♦ Prevents passing PageRank to the destination link
♦ Prevents the destination link from being crawled
♦ Does not prevent the link from being recorded as a backlink
The no follow link simply means that search engines are not giving enough weight to that link. This kind of link was invented for the purpose of cutting down the use of spam links. It is advisable then that you understand no follow links in order for you to build your own website strategy while at the same time benefiting from it.
A NoFollow link refers to backlinks that tell the search engines to not go any further (not include in PageRank) . Nofollow is an attribute that can be added to links to discourage spam ..
It just refers to such links that do not follow the desired webpage.
I do not agree that nofollow links not be crawled and if so then in google results why it show the content containing the nofollow tag with it. So definitely nofollow link be crawled and be helpful to get traffic to the site. Nofollow links just not pass on the link juice and that is why it not be helpful in the higher rank of the site. So still there is value of the nofollow link.
a link that doesn't followed by the search engine bot or spider. but according to my experience these links get indexed.
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