First time I understand about semantic URL is when I started to create my blog. According to the Wikipedia, “Semantic URL” refers to a URL which is of a form that is immediately and intuitively meaningful to non-expert. For example, if we refer to a publishing pages in SharePoint , we might see http://<someserver>/<somedepartment>/pages/default.aspx , or http://www.mycompany.com/hrdepartment/pages/policy.aspx which are not intuitive.
To make it easier for non SharePoint expert, one would love to remember semantic urls such as http://www.mycompany.com/hrdepartment/policy which then redirect to actual page under pages library in SharePoint.
Waldek has post excellent how-to , to create semantic URL in IIS-7 in his blog here. However, I wonder if we could do the same (without create single line of code) in IIS-6.