Canonical

The canonical meta tag? What is it? Let’s explain it and what it is.

Now a days some meta tags it would seem are given less weight by search engines than other tags, for instance the keyword meta tag is suspected to have no impact on a web page by google today, having said that we still put the keywords in all our pages. This is a classic example of things changing all the time! The canonical tag has been supported by google for nearly a year now but is still worth clarification as to how this may impact on a website.

The canonical meta tag was supported to give website with dynamic content or content management facilities a fair chance of being judged in the rankings game, sound confusing? Lets explain.

A website url might kick out several versions of the same page:

http://www.yourdomain.co.uk
http://www.yourdomain.co.uk/index.html
http://yourdomain.co.uk
http://yourdomain.co.uk/index.html

All these urls are the same page but they will be indexed by robots as different pages and the danger here is that the robots register duplicate content. This is potentially very bad for your website. More complicated dynamic url’s or a session ID is created when categories and search query’s are perform these are called variable url’s or ugly urls:

http://www.yourdomain.co.uk/default.aspx?item=chocolate-cakes&category=sweets
http://www.yourdomain.co.uk/default.aspx?item=category=&trackingid=1234&sessionid=5678

Ugly url’s are no good for SEO in general but lets stick to the canonical tag for now.

Do you know if your website has this problem? If you don’t you should do or get your webmaster to advise you. What happens if you do have this problem? Well your website is in danger of increasing duplicate content every time you add pages or add more content especially with content management systems and e-commerce websites.

The simple solution around this problem of duplicate content is to use the canonical meta tag <link rel=”canonical” href=”www.yourdomain.co.uk/xxx” />? in the <head> tag of all your website pages. What this does is ensure the web site is not a victim of content duplication. Web designers should be using the canonical meta tag as a standard part of web development. If you are the owner of a website and your url’s are ugly you might be losing valuable traffic to your website. Also if you can access your website by dropping all the www, adding the default index page then you might be losing traffic again in the same way due to content duplication. Check it out now, go to your website and click on the links and look at the url’s.

If the url’s are ugly then you the web designer or whoever built the site should be made aware of the problem.