A carriageway consists of a width of road

Road

A road is a thoroughfare, route, or way on land between two places, which typically has been paved or otherwise improved to allow travel by some conveyance, including a horse, cart, or motor vehicle. Roads consist of one, or sometimes two, roadways each with one or more lanes and also any...

 on which a vehicle is not restricted by any physical barriers or separation to move laterally

Lateral movement

Lateral movements or lateral flexions within equestrianism, have a specific meaning, used to refer to movements made by a horse where the animal is moving in a direction other than straight forward...

. A carriageway generally consists of a number of traffic lanes

Lane

A lane is a part of the roadway within a road marked out for use by a single line of vehicles in such a way as to control and guide drivers for the purpose of reducing traffic conflicts. Most public roads have at least two lanes, one for traffic in each direction, separated by Lane markings...

 together with any associated shoulder

Shoulder (road)

A hard shoulder, or simply shoulder, is a reserved area by the verge of a road or motorway. Generally it is kept clear of motor vehicle traffic...

, but may be a sole lane in width (for example, a highway offramp

Interchange (road)

In the field of road transport, an interchange is a road junction that typically uses grade separation, and one or more ramps, to permit traffic on at least one highway to pass through the junction without directly crossing any other traffic stream. It differs from a standard intersection, at which...

).

A single carriageway

Single carriageway

A single carriageway is a road with 1, 2 or more lanes arranged within a single carriageway with no central reservation to separate opposing flows of traffic. Two-lane road or two-lane highway are single carriageway with one lane for each direction...

 road (North American English: undivided highway) has one carriageway with 1, 2 or more lanes together with any associated footways

Sidewalk

A sidewalk, or pavement, footpath, footway, and sometimes platform, is a path along the side of a road. A sidewalk may accommodate moderate changes in grade and is normally separated from the vehicular section by a curb...

 (North American English: sidewalk) and road verges (North American English: tree lawn, boulevard, etc.). A dual carriageway

Dual carriageway

A dual carriageway is a class of highway with two carriageways for traffic travelling in opposite directions separated by a central reservation...

 road (North American English: divided highway) has two roadways separated by a central reservation

Central reservation

On divided roads, such as divided highways or freeways/motorways, the central reservation , median, parkway , median strip or central nature strip is the area which separates opposing lanes of traffic...

 (North American English: median). A local-express

Local-express lanes

A Local-express lane system is an arrangement of roadways within a major highway providing one of more roadways for express lanes with a limited number of entrances and exits and also separate roadways for local or collector lanes which provide access to all interchanges...

 lane system (also called collector-express or collector-distributor) has more than two roadways, typically two 'local lanes' or 'collector lanes' and also two 'express lanes'. High occupancy vehicle lanes may also be physically separated from the rest of the general traffic lanes into a distinct roadway.