Duplicate content is an issue when it comes to Search Engine Optimisation (SEO). If a single webpage can be accessed/indexed in several ways, then most of the search engines treat this as individual pages with duplicate content which in-turn has a negative effect in page ranking and SEO of your website.
There can be several instances which can cause this and is mainly down to how you structure your URLs across the website. The following are a few situations which can lead to duplicate content issue:
1) Both www.websitename.com and www.websitename.com/index.htm exist
2) Appending information related to filters, currency selections and session variables to your URLs.
3) Both SEO friendly and non SEO friendly URLs exist on your website.
Google and most other search engines now consider the usage of ‘canonical’ tags which can be used to mention the primary URL. Search Engines will then assume all the other variations relate to the primary URL and additional URL properties like PageRank, etc. will be transferred to the primary URL as well.
Here is an example on how to use the ‘canonical’ tag:
The following needs to be placed in the <HEAD> section of your webpage:
<link rel="canonical" href=”http://www.yoursite.com/iPhone3g.html" />
Here is an example of a website that uses ‘canonical’ tags - http://www.rugstorene.co.uk/traditional_wilton_rugs/
- Ravi Adloori
[TAGS: Google, Canonical Tags, SEO, Duplicate Page Issue, Search Engine Optimisation]