Static URLs are known to be better than Dynamic URLs because of a number of reasons:
1. Static URLs typically Rank better in Search Engines.
2. Search Engines are known to index the content of dynamic pages a lot slower compared to static pages.
3. Static URLs are always more friendlier looking to the End Users.
Example of a dynamic URL http://www.widgets.com/product.php?categoryid=1&productid=10
This tool helps you convert dynamic URLs into static looking html URLs.
Example of the above dynamic URL Re-written using this tool http://www.widgets.com/product-categoryid-1-productid-10.htm
Note*
You would need to create a file called ".htaccess" and paste the code generated into it, Once you have created the .htacess file simply copy it into your web directory.
URL rewriting of this type would work ONLY if you are hosted on a Linux Server.
Site Optimization 
