Thursday, December 17, 2009

Nofollow Questions?

Nofollow, an HTML attribute, was designed by in early 2005 Google’s Matt Cutts and Blogger’s Jason Shellen and originally intended to stop comment spam on blogs.*  Nofollow was NOT meant to block access to content or block search engines spiders from indexing sites and content. 

Search engine optimization professionals started using the NoFollow attribute to control the flow of PageRank within a website, but google since corrected this error, and any link with NoFollow attribute decreases the PR that the page can pass on. This practice is known as PageRank sculpting. This is an entirely different use than it was intended originally. NoFollow was designed to control the flow of PageRank from one website to another.*

However, while search engines supporting the attribute exclude links that use the attribute from their ranking calculation, search engines treat the NoFollow attribute a little differently.

  • Google states that their engine takes "nofollow" literally and does not "follow" the link at all. However, experiments conducted by SEOs show conflicting results. These studies reveal that Google does follow the link, but does not index the linked-to page, unless it was in Google's index already for other reasons (such as other, non-nofollow links that point to the page).
  • Yahoo! "follows it", but excludes it from their ranking calculation.
  • Bing respects "nofollow" as regards not counting the link in their ranking, but it is not proven whether or not Bing follows the link.
  • ignores the attribute altogether.*
While NoFollow has supporters and detractors, no solid evidence exists on its potential harm or usefulness.  In general, the consensus tends to favor the use of NoFollow on internal links pointing to user-controlled pages.  Our opinion is to implement NoFollow; if negative results ensue, the process can easily be reversed.

A simple tutorial we found for implementing NoFollow is found here:

- AJ

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