http://community.usatourist.com/blogs/uslife/archive/2008/06/19/long-distance-truckers.aspxWe call them eighteen wheelers. They are the large tractor-semi-trailor rigs that haul goods across the USA on the network of Interstate highways. The front part of the rig is the actual truck or tractor, while the back two thirds of the rig is reallyenCommunityServer 2007.1 (Build: 20917.1142)