SEO Glossary – N
Nofollow can be defined as HTML attribute which instruct that search engine crawler or bot that web owner of the page has decided not to pass link popularity to URL mentioned along with this attribute. Rel=”nofollow” tag is invented by Google engineers to fight with blog comment spammers. Latter on it is being used buy other search engines Yahoo and Bing . Here is an example
The tag is useful where a users can add there URL to your site. It helps in preventing search engine spam. Nofollow HTML attribute does not allow passing on the link popularity to particular link URL to which it is mentioned. It has nothing to do with whole links on a web page. Nofollow links may be useful for search engine ranking purpose but still it can drive traffic to your site. So we cannot say that nofollow links has no value at all.
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