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nofollow

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For technical documentation about nofollow as it relates to Wikimedia projects, seemeta:nofollow.

nofollowis a setting on aweb pagehyperlinkthat directssearch enginesnot to use the link forpage rankingcalculations. It is specified in the page as a type oflink relation;that is:<a rel= "nofollow"...>.Because search engines often calculate a site's importance according to the number of hyperlinks from other sites, thenofollowsetting allows website authors to indicate that the presence of a link is not an endorsement of the target site's importance.

Concept and specification

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Thenofollowvalue was originally suggested to stop commentspam in blogs.Believing that comment spam affected the entirebloggingcommunity, in early 2005Google'sMatt CuttsandBlogger'sJason Shellenproposed the value to address the problem.[1][2]

The specification fornofollowis copyrighted 2005–07 by the authors and subject to a royalty-free patent policy, e.g. per theW3CPatent Policy 20040205,[3]andIETFRFC3667and3668.[2]

Example

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<ahref="http:// example /"rel="nofollow">Link text</a>

Introduction and support

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Googleannounced in early 2005 that hyperlinks withrel= "nofollow"[4]would not influence the link target'sPageRank.[5]In addition, the Yahoo and Bing search engines also respect this attribute value.[6]

On June 15, 2009, Google software engineerMatt Cuttsannounced on his blog that GoogleBot changed the way it treats nofollowed links, in order to prevent webmasters from using nofollow for PageRank sculpting. Prior to this, webmasters would place nofollow tags on some of their links in order to maximize the PageRank of the other pages. As a result of this change, the usage of nofollow leads to the evaporation of the pagerank of outgoing normal links as they started counting total links while calculating page rank. The new system divides page rank by the total number of outgoing links irrespective of nofollow or follow links, but passes the page rank only through follow or normal links. Cutts explained that if a page has 5 normal links and 5 nofollow outgoing links, the page rank will be divided by 10 links and one share is passed by 5 normal links.[7]However, as of March 1 2020, Google is treating the nofollow link attribute as a hint, rather than a directive, for crawling and inde xing purposes.[8]

Interpretation by the individual search engines

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While all engines that use thenofollowvalue exclude links that use it from their ranking calculation, the details about the exact interpretation of it vary from search engine to search engine.[9][10]

  • Googlestates that their engine "in general" takes "nofollow" literally and does not "follow" the link.[11]
  • Yahoo!follows it, but excludes it from their ranking calculation.[12]
  • Bingmay not follow it, but they exclude it from their ranking calculation.[citation needed][13]
  • Askalso respects the attribute.[14]
  • Baiduappears to respect the attribute.[citation needed]
rel= "nofollow" Action Google Yahoo! Bing Ask Baidu
Uses the link for ranking No No No — No
Follows the link No Yes — No —
Indexes the "linked to" page No Yes No No —
Shows the existence of the link Only for a previously indexed page Yes Yes Yes —
Inresults pagesfor anchor text Only for a previously indexed page Yes Only for a previously indexed page Yes —

Use by websites

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Many weblog software packages mark reader-submitted links this way[15]by default (often with no option to disable it, except for modification of the software's code).

More sophisticated server software could suppress the nofollow for links submitted bytrusted userslike those registered for a long time, on awhitelist,or with an acceptablekarmalevel. Some server software addsrel= "nofollow"to pages that have been recently edited but omits it from stable pages, under the theory that stable pages will have had offending links removed by human editors.

The widely used blogging platformWordPressversions 1.5 and above automatically assign thenofollowattribute to all user-submitted links (comment data, commenter URI, etc.).[16]However, there are several free plugins available that automatically remove thenofollowattribute value.[17]

Social bookmarking and photo sharing websites that use therel= "nofollow"tag for their outgoing links includeYouTubeandDigg[18](for most links); websites that don't use therel= "nofollow"tag includeYahoo!My Web 2.0,TechnoratiFavs, andPropeller(no longer an active website).[19]

Repurpose

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Control internal PageRank flow

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Search engine optimization professionals started using thenofollowattribute to control the flow of PageRank within a website, but Google has since corrected this error, and any link with a nofollow attribute decreases the PageRank that the page can pass on. This practice is known as "PageRank sculpting". This is an entirely different use than originally intended.nofollowwas designed to control the flow of PageRank from one website to another. However, some SEOs have suggested that anofollowused for an internal link should work just likenofollowused for external links.

Several SEOs have suggested that pages such as "About Us", "Terms of Service", "Contact Us", and "Privacy Policy" pages are not important enough to earn PageRank, and so should havenofollowon internal links pointing to them. Google employeeMatt Cuttshas provided indirect responses on the subject, but has never publicly endorsed this point of view.[20]

The practice is controversial and has been challenged by some SEO professionals, including Shari Thurow[21]and Adam Audette.[22]Site search proponents have pointed out that visitors do search for these types of pages, so usingnofollowon internal links pointing to them may make it difficult or impossible for visitors to find these pages in site searches powered by major search engines.

Although proponents of use ofnofollowon internal links have cited an inappropriate attribution to Matt Cutts[23](see Matt's clarifying comment, rebutting the attributed statement)[24]as support for using the technique, Cutts himself never actually endorsed the idea. Several Google employees (including Matt Cutts) have urged Webmasters not to focus on manipulating internal PageRank. Google employeeAdam Lasnik[25]has advised webmasters that there are better ways (e.g.click hierarchy) thannofollowto "sculpt a bit of PageRank", but that it is available and "we're not going to frown upon it".

YouTube,a Google company, uses nofollow on a number of internal "help" and "share" links.[26]

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On September 10, 2019, Google announced[27][28]two additional ways for webmasters to qualify the relationship of outbound hyperlinks. The attributerel= "sponsored"may be used to denote links that are advertisements, sponsorships or other compensation agreements. The attributerel= "ugc",standing for "User-generated content",may be used to denote content such as user-contributed comments and forum posts. Additionally, the attributes may be combined, such asrel= "ugc sponsored",denoting a link that was both user-generated and sponsored. In 2019, WordPress announced plans to convert all blog comments into rel= "ugc".[29]

These "hint" link attributes address some of the criticisms ofnofollowby allowing webmasters to denote outbound links that lack "the weight of a first-party endorsement", but are not necessarily spam.

See also

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Blocking and excluding content from search engines

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References

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  1. ^The nofollow Attribute and SEO,archived fromthe originalon 2011-07-15
  2. ^ab"rel=" nofollow "".Microformats Wiki.10 Jan 2005.RetrievedJune 17,2007.
  3. ^"W3C Patent Policy".W3C.2004-02-05.
  4. ^"Links in HTML documents".W3C.rel = link-types.RetrievedMay 29,2007.
  5. ^"Preventing comment spam".Official Google Blog.2005-01-18.RetrievedMay 29,2007.
  6. ^"robots exclusion protocol: joining together to provide better documentation".Bing Community.June 3, 2008. Archived fromthe originalon 2009-06-11.RetrievedJune 11,2009.
  7. ^"PageRank sculpting".Matt Cutts: Gadgets, Google, and SEO.2009-06-16.
  8. ^Nguyen, George (2020-02-28)."Google's new treatment of nofollow links has arrived".Search Engine Land.
  9. ^Baker, Loren (April 29, 2007)."How Google, Yahoo & Ask Treat the No Follow Link Attribute".Search Engine Journal.Archived from the original on 2007-04-28.RetrievedMay 29,2007.{{cite web}}:CS1 maint: unfit URL (link)
  10. ^Duz, Michael (December 2, 2006)."rel=" nofollow "Google, Yahoo and MSN".SEO Blog.Archived fromthe originalon June 2, 2007.RetrievedMay 29,2007.
  11. ^"Use rel=" nofollow "for specific links - Search Console Help".support.google.Archived fromthe originalon 2017-10-04.Retrieved2018-01-15.
  12. ^"How Google, Yahoo & Ask Treat the No Follow Link Attribute - Search Engine Journal".searchenginejournal.29 April 2007.
  13. ^"Dofollow And Nofollow Links In SEO".Beta Compression.Retrieved2017-03-18.
  14. ^"Webmasters".About Ask. Archived from the original on 2012-07-07.Retrieved2012-01-09.{{cite web}}:CS1 maint: unfit URL (link)
  15. ^"Preventing comment spam".Official Google Blog.2005-01-18.RetrievedSeptember 28,2010.
  16. ^"Nofollow".WordPress Codex.2005-05-23.RetrievedMay 29,2007.
  17. ^"Plugins categorized as nofollow".WordPress.org.RetrievedMarch 10,2008.
  18. ^Quinn, John (September 2, 2009)."Recent Changes to NOFOLLOW on External Links".Digg the Blog.Archived fromthe originalon 2009-09-06.RetrievedSeptember 3,2009.
  19. ^Baker, Loren (November 15, 2007)."Social Bookmarking Sites Which Don't Use NoFollow Bookmarks and Search Engines".Search Engine Journal.Archived from the original on 2007-11-16.RetrievedDecember 16,2007.{{cite web}}:CS1 maint: unfit URL (link)
  20. ^October 8, 2007,Eric Enge Interviews Google's Matt Cutts,Stone Temple Consulting,retrieved on January 20, 2008.
  21. ^Thurow, Shari. March 6, 2008,You'd be wise to "nofollow" this dubious advice,Search Engine Land.
  22. ^June 3, 20088 Arguments Against Sculpting PageRank With NofollowArchived2008-08-08 at theWayback Machine,Audette Media.
  23. ^August 29, 2007Matt Cutts on Nofollow, Links-Per-Page and the Value of Directories,Moz (marketing software).
  24. ^August 29, 2007Moz,SEOmoz comment by Matt Cutts.
  25. ^February 20, 2008Interview with Adam Lasnik of Google
  26. ^"Nofollow Reciprocity".Inverudio. 2010-01-28.Retrieved2012-01-09.
  27. ^"Evolving" nofollow "– new ways to identify the nature of links".Official Google Webmaster Central Blog.Retrieved2019-09-12.
  28. ^"Qualify your outbound links to Google - Search Console Help".support.google.Retrieved2019-09-12.
  29. ^"WordPress 5.3 Adopts Rel UGC Nofollow Link Attribute".Search Engine Journal.2019-10-04.Retrieved2019-10-04.
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