ModX references everything by its ID number e.g., index.php?id=50. Even when using aliases it seems to be restricted to 1 layer. See their documentation section. I just had a play on the demo and I couldn't even get to my test page because it didn't show up in the menus.
Drupal appears to use the same /module/function/parameter/ format as other CMSs e.g., /node/20/. Looks quite powerful/customisable/complication.