A shared edge is an edge that is owned, or shared, by two adjacent surfaces.
Shared edges are colored green by default.
When the edge between two surfaces is a shared edge, there is no gap or overlap between the two surfaces - they are geometrically continuous. The automesher always places seed nodes along the length a shared edge and will produce a continuous mesh without any gaps along that edge. The automesher will not construct any individual elements that cross over a shared edge.