The pages are dynamic but search engines friendly URLs option can be enabled if Apache module mod_rewrite is installed,
so most important website pages look to visitors and search engines like static HTML pages.
If your URLs looks like HTML pages (e.g. page-XX.html, browse-XX-XX.html) it means you checked on "Enable search engines friendly URLs" option in Admin Area -> Application Setup -> Advanced Setup.
You need Apache module "mod_rewrite" installed for this...