Duplicate Content

Duplicate content is often a big problem on many sites. It is usually that it is created more of the same pages, and this is a result of many CMS that is not working perfectly or that you have not thought about it when you built the site. The main reason it is bad with duplicate content is that you are not stringently in internal linking and therefore spreading link power to unnecessary pages. Google is also trying to filter so that only one site of each count, so if you are unlucky the wrong site is filtered out. This also affects if you have the same content as another website.

Perhaps the most common example with duplicated content is that you can come to the same site with and without www. What you should do is  a 301 redirect from one to the other. So that if someone types www.domain.com, and you have decided the site should be without, the visitor gets redirected automatically to the domain without the www. Another common error is to be linked to the index.html in navigation instead of the domain when you want to point to the home page, then Google see it as two different pages with the same content, this is of course not good.

If you are careful when you think through the structure of the website usually you don’t have any problems with this, but there are some things you might not think of. Category and tag pages for example, they can often show the same content as on the actual page. It creates the same problem with duplicate content. Often we solve it by putting noindex (in robots.txt)  for search engines.

An example of when it can go very wrong with duplicate content is when you have your own affiliate system that is not working perfectly. The usual way to track visitors to the affiliate system is that each affiliate each get a landing page with an affiliate. It might look something like this; domain.com/affiliate?=ID842 or similar. It is easy to choose to view a copy of the page with the trackingID so that visitors coming from the affiliate continues to have the same ID in all paths. It will generate an exact copy of the website according to the search engines, and if you use many affiliates you can create many copies.  Not only do you get anything from the link, but you actually damaging the site significantly.

The right way to handle affiliate links is to use a tracking cookie and then a 301 redirect to the correct page. Then the webpage will and you do not create a lot of duplicate content.