Canonical Link Structuring
For anyone running a website, search engine optimization is always a smoking hot topic and there are a million things to do as a business owner or website operator that can all add value to your website in the eyes of search engines everywhere. Now, I don’t make the claim to be an SEO expert because quite frankly I’m not but there are concepts that come around every so often that knock the traditional limitations of great search engine optimization on their ear.
Canonicals aka “Canonical Links” or “Canonical Link Relationships” were released about a year ago and CMS and ecommerce software vendors like WordPress, Durpal, Magento Commerce and countless others have been quick to offer enhancements incorporating this standard for structuring linking relationships of web pages and content in a given web site to help search engines better index web pages.
What in the hell is a canonical link?
No, it’s not a camera or an appendage on a sea creature but rather it’s a linking relationship that allows search engines to figure out what web page is the original and which web pages are duplicates of the original. Before this came around, duplicate content on websites was known to affect page ranking and the health of the website when search engines are involved because search engines aren’t smart enough to figure out what web pages are duplicate content and which is the original content. So someone came up with the bright idea, “Hey there must be a way to tell search engines what is the original page is and which web pages are duplicate pages?” and with that canonicals were born.
Since then there have been a number of plug-ins and add-ons for people to stop this problem but before I get to that I want to help you understand what a canonical is exactly and what problem do canonical links solve exactly.
The problems that canonicals solve are that they allow search engines to know which web page they (the search engine) should index because traditionally search engines need to be told what to index, when to index it and how often to come back and index it. Other than that, a canonical link relationship allows you to direct link metrics like authority, trust, etc. to a specific web page to separate it between multiple versions of a web page.
Simply put, you can tell search engines with improved accuracy how to index a web page and this is done to solve the problem that websites have with duplicate content currently. One way that duplicate content is created is because of things like a web page being available under multiple categories and having multiple paths on a web site to the same content. So let’s assume that you sell widgets on your ecommerce website and you have these widgets available under a few categories including “Specials”, “Widgets” and “Featured Widgets”. When you associate one web page under 3 categories traditionally you create 3 separate paths to the same web page like this…
http://www.mystore.com/specials/Widget01.html
http://www.mystore.com/widgets/Widget01.html
http://www.mystore.com/featured-widgets/Widget01.html
So you have a few ways that people visiting your website can find your widget for sale. What a canonical link relationship allows you to do is specify which of the three paths above is the original web page and tell the search engines to index this instance of the web page and it’s done using a piece of code that looks a little something like this…
<link rel=”canonical” href=”http://www.mystore.com/widgets/Widget01.html” />
Aside from this, there are a few other ways that duplicate or “highly similar” content is created including when URL parameters in a URL generate the same or similar content and when session IDs are created for new visitors to a website that are visiting the same web page multiple times. So that is the idea behind why canonical link relationships are so important for solid SEO purposes.
There are a number of great articles from industry experts that present some different perspectives on the canonical link relationship and the ways that you can use it to help how your website is indexed by search engines from Matt Cutts to Joost De Valk of Yoast.com that I think are worth mentioning here. Free feel to read them if you are looking for more information about canonicals.
If you are surfing for more information about canonicals then you are bound to run into many similar terms that are being used to describe how canonicals work and how industry experts have used them but I wanted to define them in easy to use terms that just make sense.
A “Canonical Link Relationship” is the link relationship that is established on content that is the preferred page and URL of content that is used by search engines to index the web page.
A “Canonical URL” also known as “Canonical URL tag” is the preferred URL of a set of highly similar URLs to web pages in a website. This helps to fix the problem of duplicate links to the same or similar content on a website and is also what search engines use as part of the indexing taking place of the URL.
A “Canonical Page” is the preferred page of a set of highly similar pages of content on a website meaning that this is the page that Google, Bing, Yahoo! and other search engines recognize the canonical link relationship and will index this page for the search engine.
A Note about 301 redirects
Now you might be thinking that 301 redirects should solve the problem of dealing with duplicate content on a website and there are similarities for sure but some of the key differences between using a “quick and dirty” 301 redirect versus a canonical link relationship are that…
The 301 redirect, redirects everyone from visitors to search engines (spiders and robots) and the canonical link simply tells the search engine how to view the page for indexing purposes meaning that you don’t need to restrict how visitors navigate the content on your site which can definitely be a huge bonus.
And…
Redirects allow you to set redirects across different root domain names from say www.yoursite01.com to www.theirsite01.com whereas the canonicals operate and are contained entirely on only one domain name.
Canonicals aka “Canonical Links” or “Canonical Link Relationships” were released about a year ago and CMS and ecommerce software vendors like WordPress, Durpal, Magento Commerce and countless others have been quick to offer enhancements incorporating this standard for structuring linking relationships of web pages and content in a given web site to help search engines better index web pages.
What in the hell is a canonical link?
No, it’s not a camera or an appendage on a sea creature but rather it’s a linking relationship that allows search engines to figure out what web page is the original and which web pages are duplicates of the original. Before this came around, duplicate content on websites was known to affect page ranking and the health of the website when search engines are involved because search engines aren’t smart enough to figure out what web pages are duplicate content and which is the original content. So someone came up with the bright idea, “Hey there must be a way to tell search engines what is the original page is and which web pages are duplicate pages?” and with that canonicals were born.
Since then there have been a number of plug-ins and add-ons for people to stop this problem but before I get to that I want to help you understand what a canonical is exactly and what problem do canonical links solve exactly.
The problems that canonicals solve are that they allow search engines to know which web page they (the search engine) should index because traditionally search engines need to be told what to index, when to index it and how often to come back and index it. Other than that, a canonical link relationship allows you to direct link metrics like authority, trust, etc. to a specific web page to separate it between multiple versions of a web page.
Simply put, you can tell search engines with improved accuracy how to index a web page and this is done to solve the problem that websites have with duplicate content currently. One way that duplicate content is created is because of things like a web page being available under multiple categories and having multiple paths on a web site to the same content. So let’s assume that you sell widgets on your ecommerce website and you have these widgets available under a few categories including “Specials”, “Widgets” and “Featured Widgets”. When you associate one web page under 3 categories traditionally you create 3 separate paths to the same web page like this…
http://www.mystore.com/specials/Widget01.html
http://www.mystore.com/widgets/Widget01.html
http://www.mystore.com/featured-widgets/Widget01.html
So you have a few ways that people visiting your website can find your widget for sale. What a canonical link relationship allows you to do is specify which of the three paths above is the original web page and tell the search engines to index this instance of the web page and it’s done using a piece of code that looks a little something like this…
<link rel=”canonical” href=”http://www.mystore.com/widgets/Widget01.html” />
Aside from this, there are a few other ways that duplicate or “highly similar” content is created including when URL parameters in a URL generate the same or similar content and when session IDs are created for new visitors to a website that are visiting the same web page multiple times. So that is the idea behind why canonical link relationships are so important for solid SEO purposes.
There are a number of great articles from industry experts that present some different perspectives on the canonical link relationship and the ways that you can use it to help how your website is indexed by search engines from Matt Cutts to Joost De Valk of Yoast.com that I think are worth mentioning here. Free feel to read them if you are looking for more information about canonicals.
If you are surfing for more information about canonicals then you are bound to run into many similar terms that are being used to describe how canonicals work and how industry experts have used them but I wanted to define them in easy to use terms that just make sense.
A “Canonical Link Relationship” is the link relationship that is established on content that is the preferred page and URL of content that is used by search engines to index the web page.
A “Canonical URL” also known as “Canonical URL tag” is the preferred URL of a set of highly similar URLs to web pages in a website. This helps to fix the problem of duplicate links to the same or similar content on a website and is also what search engines use as part of the indexing taking place of the URL.
A “Canonical Page” is the preferred page of a set of highly similar pages of content on a website meaning that this is the page that Google, Bing, Yahoo! and other search engines recognize the canonical link relationship and will index this page for the search engine.
A Note about 301 redirects
Now you might be thinking that 301 redirects should solve the problem of dealing with duplicate content on a website and there are similarities for sure but some of the key differences between using a “quick and dirty” 301 redirect versus a canonical link relationship are that…
The 301 redirect, redirects everyone from visitors to search engines (spiders and robots) and the canonical link simply tells the search engine how to view the page for indexing purposes meaning that you don’t need to restrict how visitors navigate the content on your site which can definitely be a huge bonus.
And…
Redirects allow you to set redirects across different root domain names from say www.yoursite01.com to www.theirsite01.com whereas the canonicals operate and are contained entirely on only one domain name.