The "roads have only one name" rings very true for me. I usually denote my road as "S Hwy X" (where X is a letter, not a number). But over the years the official USPS designation has changed slightly and different organizations have different naming standards, ranging from "Highway X" to "South County Rd X" etc. One time while attempting to make a credit card payment I discovered that the vendor validated the billing address against both my bank AND the USPS standard, which were doomed to never agree. Needless to say I did not end up buying anything from them.