Nofollow

Last updated

nofollow is a setting on a web page hyperlink that directs search engines not to use the link for page ranking calculations. It is specified in the page as a type of link relation; that is: <a rel="nofollow" ...>. Because search engines often calculate a site's importance according to the number of hyperlinks from other sites, the nofollow setting allows website authors to indicate that the presence of a link is not an endorsement of the target site's importance.

Contents

Concept and specification

The nofollow value was originally suggested to stop comment spam in blogs. Believing that comment spam affected the entire blogging community, in early 2005 Google's Matt Cutts and Blogger's Jason Shellen proposed the value to address the problem. [1] [2]

The specification for nofollow is copyrighted 2005–07 by the authors and subject to a royalty-free patent policy, e.g. per the W3C Patent Policy 20040205, [3] and IETF RFC   3667 and 3668. [2]

Example

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

Introduction and support

Google announced in early 2005 that hyperlinks with rel="nofollow" [4] would not influence the link target's PageRank. [5] In addition, the Yahoo and Bing search engines also respect this attribute value. [6]

On June 15, 2009, Google software engineer Matt Cutts announced 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 indexing purposes. [8]

Interpretation by the individual search engines

While all engines that use the nofollow value 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]

rel="nofollow" ActionGoogleYahoo!BingAsk.comBaidu
Uses the link for rankingNoNoNo—No
Follows the linkNoYes—No—
Indexes the "linked to" pageNoYesNoNo—
Shows the existence of the linkOnly for a previously indexed pageYesYesYes—
In results pages for anchor textOnly for a previously indexed pageYesOnly for a previously indexed pageYes—

Use by websites

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 by trusted users like those registered for a long time, on a whitelist, or with an acceptable karma level. Some server software adds rel="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 platform WordPress versions 1.5 and above automatically assign the nofollow attribute to all user-submitted links (comment data, commenter URI, etc.). [16] However, there are several free plugins available that automatically remove the nofollow attribute value. [17]

Social bookmarking and photo sharing websites that use the rel="nofollow" tag for their outgoing links include YouTube and Digg.com [18] (for most links); websites that don't use the rel="nofollow" tag include Yahoo! My Web 2.0, Technorati Favs, and Propeller.com (no longer an active website). [19]

Repurpose

Control internal PageRank flow

Search engine optimization professionals started using the nofollow attribute 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. nofollow was designed to control the flow of PageRank from one website to another. However, some SEOs have suggested that a nofollow used for an internal link should work just like nofollow used 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 have nofollow on internal links pointing to them. Google employee Matt Cutts has 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 using nofollow on 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 of nofollow on 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 employee Adam Lasnik [25] has advised webmasters that there are better ways (e.g. click hierarchy) than nofollow to "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]

On September 10, 2019, Google announced [27] [28] two additional ways for webmasters to qualify the relationship of outbound hyperlinks. The attribute rel="sponsored" may be used to denote links that are advertisements, sponsorships or other compensation agreements. The attribute rel="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 as rel="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 of nofollow by allowing webmasters to denote outbound links that lack "the weight of a first-party endorsement", but are not necessarily spam.

See also

Blocking and excluding content from search engines

Related Research Articles

Meta elements are tags used in HTML and XHTML documents to provide structured metadata about a Web page. They are part of a web page's head section. Multiple Meta elements with different attributes can be used on the same page. Meta elements can be used to specify page description, keywords and any other metadata not provided through the other head elements and attributes.

Spamdexing is the deliberate manipulation of search engine indexes. It involves a number of methods, such as link building and repeating related and/or unrelated phrases, to manipulate the relevance or prominence of resources indexed in a manner inconsistent with the purpose of the indexing system.

A web directory or link directory is an online list or catalog of websites. That is, it is a directory on the World Wide Web of the World Wide Web. Historically, directories typically listed entries on people or businesses, and their contact information; such directories are still in use today. A web directory includes entries about websites, including links to those websites, organized into categories and subcategories. Besides a link, each entry may include the title of the website, and a description of its contents. In most web directories, the entries are about whole websites, rather than individual pages within them. Websites are often limited to inclusion in only a few categories.

Search engine optimization (SEO) is the process of improving the quality and quantity of website traffic to a website or a web page from search engines. SEO targets unpaid traffic rather than direct traffic or paid traffic. Unpaid traffic may originate from different kinds of searches, including image search, video search, academic search, news search, and industry-specific vertical search engines.

<span class="mw-page-title-main">Link farm</span> Group of websites that link to each other

On the World Wide Web, a link farm is any group of websites that all hyperlink to other sites in the group for the purpose of increasing SEO rankings. In graph theoretic terms, a link farm is a clique. Although some link farms can be created by hand, most are created through automated programs and services. A link farm is a form of spamming the index of a web search engine. Other link exchange systems are designed to allow individual websites to selectively exchange links with other relevant websites, and are not considered a form of spamdexing.

<span class="mw-page-title-main">Googlebot</span> Web crawler used by Google

Googlebot is the web crawler software used by Google that collects documents from the web to build a searchable index for the Google Search engine. This name is actually used to refer to two different types of web crawlers: a desktop crawler and a mobile crawler.

From the point of view of a given web resource (referent), a backlink is a regular hyperlink on another web resource that points to the referent. A web resource may be a website, web page, or web directory.

The anchor text, link label, or link text is the visible, clickable text in an HTML hyperlink. The term "anchor" was used in older versions of the HTML specification for what is currently referred to as the "a element", or <a>. The HTML specification does not have a specific term for anchor text, but refers to it as "text that the a element wraps around". In XML terms, the anchor text is the content of the element, provided that the content is text.

Microformats (μF) are a set of defined HTML classes created to serve as consistent and descriptive metadata about an element, designating it as representing a certain type of data. They allow software to process the information reliably by having set classes refer to a specific type of data rather than being arbitrary.

Sitemaps is a protocol in XML format meant for a webmaster to inform search engines about URLs on a website that are available for web crawling. It allows webmasters to include additional information about each URL: when it was last updated, how often it changes, and how important it is in relation to other URLs of the site. This allows search engines to crawl the site more efficiently and to find URLs that may be isolated from the rest of the site's content. The Sitemaps protocol is a URL inclusion protocol and complements robots.txt, a URL exclusion protocol.

The sandbox effect is a theory about the way Google ranks web pages in its index. It is the subject of much debate—its existence has been written about since 2004, but not confirmed, with several statements to the contrary.

<span class="mw-page-title-main">Matt Cutts</span> American software engineer

Matthew Cutts is an American software engineer. Cutts is the former Administrator of the United States Digital Service. He was first appointed as acting administrator, to later be confirmed as full administrator in October 2018. Cutts previously worked with Google as part of the search quality team on search engine optimization issues. He is the former head of the web spam team at Google.

An SEO contest is a prize activity that challenges search engine optimization (SEO) practitioners to achieve high ranking under major search engines such as Google, Yahoo, and MSN using certain keyword(s). This type of contest is controversial because it often leads to massive amounts of link spamming as participants try to boost the rankings of their pages by any means available. The SEO competitors hold the activity without the promotion of a product or service in mind, or they may organize a contest in order to market something on the Internet. Participants can showcase their skills and potentially discover and share new techniques for promoting websites.

<span class="mw-page-title-main">HTTP referer</span> HTTP header field

In HTTP, "Referer" is an optional HTTP header field that identifies the address of the web page from which the resource has been requested. By checking the referrer, the server providing the new web page can see where the request originated.

In the field of search engine optimization (SEO), link building describes actions aimed at increasing the number and quality of inbound links to a webpage with the goal of increasing the search engine rankings of that page or website. Briefly, link building is the process of establishing relevant hyperlinks to a website from external sites. Link building can increase the number of high-quality links pointing to a website, in turn increasing the likelihood of the website ranking highly in search engine results. Link building is also a proven marketing tactic for increasing brand awareness.

<span class="mw-page-title-main">PageRank</span> Algorithm used by Google Search to rank web pages

PageRank (PR) is an algorithm used by Google Search to rank web pages in their search engine results. It is named after both the term "web page" and co-founder Larry Page. PageRank is a way of measuring the importance of website pages. According to Google:

PageRank works by counting the number and quality of links to a page to determine a rough estimate of how important the website is. The underlying assumption is that more important websites are likely to receive more links from other websites.

XRumer is a piece of software made for spamming online forums and comment sections. It is marketed as a program for search engine optimization and was created by BotmasterLabs. It is able to register and post to forums with the aim of boosting search engine rankings. The program is able to bypass security techniques commonly used by many forums and blogs to deter automated spam, such as account registration, client detection, many forms of CAPTCHAs, and e-mail activation before posting. The program utilises SOCKS and HTTP proxies in an attempt to make it more difficult for administrators to block posts by source IP, and features a proxy checking tool to verify the integrity and anonymity of the proxies used.

A canonical link element is an HTML element that helps webmasters prevent duplicate content issues in search engine optimization by specifying the "canonical" or "preferred" version of a web page. It is described in RFC 6596, which went live in April 2012.

Google Penguin is a codename for a Google algorithm update that was first announced on April 24, 2012. The update was aimed at decreasing search engine rankings of websites that violate Google's Webmaster Guidelines by using now declared Grey Hat SEM techniques involved in increasing artificially the ranking of a webpage by manipulating the number of links pointing to the page. Such tactics are commonly described as link schemes. According to Google's John Mueller, as of 2013, Google announced all updates to the Penguin filter to the public.

Google Search, offered by Google, is the most widely used search engine on the World Wide Web as of 2023, with over eight billion searches a day. This page covers key events in the history of Google's search service.

References

  1. ↑ The nofollow Attribute and SEO, archived from the original on 2011-07-15
  2. 1 2 "rel="nofollow"". Microformats Wiki. 10 Jan 2005. Retrieved June 17, 2007.
  3. ↑ "W3C Patent Policy". W3C. 2004-02-05.
  4. ↑ "Links in HTML documents". W3C. rel = link-types. Retrieved May 29, 2007.
  5. ↑ "Preventing comment spam". Official Google Blog. 2005-01-18. Retrieved May 29, 2007.
  6. ↑ "robots exclusion protocol: joining together to provide better documentation". Bing Community. June 3, 2008. Archived from the original on 2009-06-11. Retrieved June 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.com Treat the No Follow Link Attribute". Search Engine Journal. Archived from the original on 2007-04-28. Retrieved May 29, 2007.{{cite web}}: CS1 maint: unfit URL (link)
  10. ↑ Duz, Michael (December 2, 2006). "rel="nofollow" Google, Yahoo and MSN". SEO Blog. Archived from the original on June 2, 2007. Retrieved May 29, 2007.
  11. ↑ "Use rel="nofollow" for specific links - Search Console Help". support.google.com. Archived from the original on 2017-10-04. Retrieved 2018-01-15.
  12. ↑ "How Google, Yahoo & Ask.com Treat the No Follow Link Attribute - Search Engine Journal". searchenginejournal.com. 29 April 2007.
  13. ↑ "Dofollow And Nofollow Links In SEO". Beta Compression. Retrieved 2017-03-18.
  14. ↑ "Webmasters". About Ask.com. Archived from the original on 2012-07-07. Retrieved 2012-01-09.{{cite web}}: CS1 maint: unfit URL (link)
  15. ↑ "Preventing comment spam". Official Google Blog. 2005-01-18. Retrieved September 28, 2010.
  16. ↑ "Nofollow". WordPress Codex. 2005-05-23. Retrieved May 29, 2007.
  17. ↑ "Plugins categorized as nofollow". WordPress.org. Retrieved March 10, 2008.
  18. ↑ Quinn, John (September 2, 2009). "Recent Changes to NOFOLLOW on External Links". Digg the Blog. Archived from the original on 2009-09-06. Retrieved September 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. Retrieved December 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, 2008 8 Arguments Against Sculpting PageRank With Nofollow Archived 2008-08-08 at the Wayback Machine , Audette Media.
  23. ↑ August 29, 2007 Matt Cutts on Nofollow, Links-Per-Page and the Value of Directories, Moz (marketing software).
  24. ↑ August 29, 2007 Moz, SEOmoz comment by Matt Cutts.
  25. ↑ February 20, 2008 Interview with Adam Lasnik of Google
  26. ↑ "Nofollow Reciprocity". Inverudio.com. 2010-01-28. Retrieved 2012-01-09.
  27. ↑ "Evolving "nofollow" – new ways to identify the nature of links". Official Google Webmaster Central Blog. Retrieved 2019-09-12.
  28. ↑ "Qualify your outbound links to Google - Search Console Help". support.google.com. Retrieved 2019-09-12.
  29. ↑ "WordPress 5.3 Adopts Rel UGC Nofollow Link Attribute". Search Engine Journal. 2019-10-04. Retrieved 2019-10-04.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.