Any presentations on Blogging and Blogsites always seems to mention that a major benefit of a Blog is the SEO advantages of Long Tail URLs.

But What is a Long Tail URL?

The term "long tail" refers to a type of statistical distribution where the frequency of a result gets smaller and smaller until it gradually "tails off.

In other words, when considering traffic to a website, a small number of URLs are responsible for a large quantity of visitors to your site - whereas a greater number of other URLs attract a decreasingly smaller volume of traffic.

So,"Long Tail URLs" refer to the collection of URLs that only attract small amounts of traffic, which are in the 'long tail' of the graph that shows volume of traffic by each web page.

So What?

Well, it turns out that many "long tail URLs" are very specific pages. For example, a blog article that has a URL  like this:

http://blog.singlepropertysites.com/2009/12/add-sponsors-and-banner-ads-with-campaigns/

This is a highly specific URL. It is ranked number 2 in Google for the keywords "sponsors banner ads campaigns", which is a "long-tail keyword". Someone searching using this keyword phrase has a very specific requirement indeed! They will definitely find this webpage!

And this is where the Return on Investment lies: Because long-tail key words are much more specific than the shorter-tail keywords, the long tail ones give us a greater opportunity to present relevant content to the searcher, to keep their interest, and hopefully turn them into a sales lead!

So, the articles that you write will contain many permutations of keywords, which creates many pages that are Long Tail URLs.

In summary - Long Tail URLs give you an opportunity to engage motivated consumers and ultimately see higher conversion rates.

Want to read More?

Check out Chris Andersons Article from 2004.

More complete references on Long Tail URLs at Wikipedia