High-definition map

A high-definition map (HD map) is a highly accurate map made for self-driving cars. They have things not present on traditional maps. HD maps are accurate at a centimetre level.
HD maps are made using different sensors. These sensors include LiDARs, radars, digital cameras and GPS. HD maps can also be made using aerial imagery.
High-definition maps can include things like road shape, road marking, traffic signs and barriers.