Joomla, as a PHP/MySQL powered solution is inserting the content into a webpage by way of a script. This type of site is considered to be dynamic. The advantage is obvious - that's why you and me have been chosen Joomla Tongue out. But what's the drawback?
There are two types of URLs: dynamic and static. A dynamic URL is a page address that results dynamically from the search of a database-driven web site or the URL of a web site that runs a script. In contrast to static URLs, in which the contents of the web page stay the same unless the changes are hard-coded into the HTML, dynamic URLs are generated from specific queries to a site's database. The dynamic page as Joomla is basically only a template in which are displayed the results of the database queryes. Instead of changing information in the HTML code, the data is changed in the database.
But there is a risk when using dynamic URLs: search engines don't like them. Among the sites at most risk of losing search engine positioning due to dynamic URLs as e-commerce stores, forums, sites utilizing content management systems and blogs like WordPress are on top position the Joomla sites. You already may know, that your URL's are looking something like this:
A static URL on the other hand, is a URL that doesn't change, and doesn't have variable strings. It looks like this:
Static URLs are typically ranked better in search engine results pages, and they are indexed more quickly than dynamic URLs, if dynamic URLs get indexed at all. Static URLs are also easier for the end-user to view and understand what the page is about. If a user sees a URL in a search engine query that matches the title and description, they are more likely to click on that URL than one that doesn't make sense to them.
A search engine wants to only list pages its index that are unique. Search engines decide to combat this issue by cutting off the URLs after a specific number of variable strings (e.g.: ? & =).
For example, let's look at three URLs:
http://www.yoursite.com/index.php?option=com_content&Itemid=37&id=16§ionid=8&task=category http://www.yoursite.com/index.php?option=com_content&Itemid=38&id=16§ionid=8&task=category http://www.yoursite.com/index.php?option=com_content&Itemid=37&id=16§ionid=9&task=category
Although they're looking pretty similar, as a Joomla webmaster you know that these are pointing to 3 different pages. But your visitors? Search engines are trying to help them, cutting the "non-relevant" parts of the URL. But if the search engine purges the information after the first offending character, the question mark (?), now all three pages look the same:
http://www.yoursite.com/index.php?option=com_content http://www.yoursite.com/index.php?option=com_content http://www.yoursite.com/index.php?option=com_content
Now, you don't have unique pages, and consequently, the duplicate URL's won't be indexed.
Another issue is that the dynamic pages generated by Joomla generally do not have any keywords in the URL. It is very important to have keyword rich URL's SEO wise. Highly relevant keywords should appear in the domain name or the page URL. This became clear in a recent study (2009) on how the top three search engines, Google, Yahoo, and MSN/Bing, rank websites.
The study involved taking hundreds of highly competitive keyword queries, like travel, cars, and computer software, and comparing factors involving the top ten results. The statistics show that of those top ten, Google has 40-50% of those with the keyword either in the URL or the domain; Yahoo shows 60%; and MSN/Bing has an astonishing 85%! What that means is that to these search engines, having your keywords in your URL or domain name could mean the difference between a top ten ranking, and a ranking far down in the results pages.
What you can do?
The answer is simple: use the available SEO tools/enhancements for Joomla, and/or ask a Joomla SEO expert to help you.
The choices are more, than one, from the built-in SEF friendly URL generation (not bad, but not enough) to different Joomla SEF components (as sh404SEF, my personal favorite), free or commercial, keyword enhancers, bots, modules you can find a lot of things to help you!
Take a look around on the web, and make your choice today!