> 1: I'm unsure what constitutes a highway, what is the difference (if there's any) to an interstate and .. what you'd call the 'normal' roads between cities.

> 1: I'm unsure what constitutes a highway, what is the difference (if there's any) to an interstate and .. what you'd call the 'normal' roads between cities. Very generally speaking, interstates are federally-funded/built longer roads (I-10, for example, spans from Florida to California, but there often shorter offshoots) that are usually at least four lanes total (almost always much more in metropolitian areas) and do not have stoplights, stop signs, or any cross traffic at all. Access is controlled by marked exits. The usual speed limit is 70 mph, sometimes lower or higher, often much lower in metropolitian areas with lots of exits and therefore merging. It really depends on the area, congestion, and the actual speed limit but in my experience people more commonly drive ~80mph on the interstate, at least where the speed limit is 70mph. Highways are pretty much a broad spectrum. They are usually paid for and maintained by the states (although federal grants are common). Sometimes access is controlled for short stretches, but in general they have stoplights and stop signs. They are usually multi-lane and often the major throroughfares through a city are a highway. Speed limits vary wildly. There are two lane country-road highways with few stops and 10 lane metropolitan highways with stops every 100 feet. They tend to be fairly long but not always. "Other" is pretty much the final category, which includes city streets and country roads. They usually aren't very long; any sufficiently long road is usually transformed into a highway if it isn't already. The "normal" roads between cities are almost always interstates and highways.