A highway is a major thoroughfare connecting any two or more points. Highways may have traffic lights, intersections and railroad crossings.
A freeway is a multilane, limited-access highway, on which cars generally travel at high speeds. A freeway has no intersections, stop lights or railroad crossings. All cross-traffic on a freeway passes via overpass or underpass. Freeways were originally named because they allow traffic to flow freely in a single direction.
Other terms for freeway include expressway, turnpike, interstate highway, and thruway. Also, as a highway is a fitting term for any major road, it is correct to refer to a freeway as a highway.
