OS Open Roads features are classified into three feature types. Each feature type has associated attribution and further detail of this can be found in the OS Open Roads Technical Specification.
These are the descriptions for each feature type:
RoadLink – This feature represents the generalised alignment of the road carriageway. It can represent either part or all of a road. Links end where there is a change in attribution or at a junction. Where a RoadLink crosses over another RoadLink, for example at a bridge, neither link will be split. Each end of a RoadLink's geometry is coincident with a RoadNode.
RoadNode – This feature represents a junction, roundabout, change in attribution, or the end of a road. The geometry of a RoadNode is coincident with the end of related links.
MotorwayJunction – This is a point feature representing the generalised location of a motorway junction. It provides information on the motorway number and the junction number, for example M42 J2. Where two motorway junctions meet, for example, M3 J2 and M25 J12, there will be two MotorwayJunction features, one representing each junction.