The DSM process creates an object called a Point Cloud and optionally a Triangulated Mesh. The Mesh is generated from the Point Cloud. A Point Cloud is cloud of 3D points and the Triangulated Mesh is the triangulated surface generated from it. So they’re closely related.
In PhotoModeler, a Triangulated Mesh is referred to as a Mesh or Mesh Surface or Triangulated Mesh, but if it’s not triangulated, it is simply referred to as a Point Cloud.
The DSM process generates a dense Point Cloud and to convert it to a useful triangulated surface, some meshing tools need to be run. The meshing tools can be run as an automatic second step after the DSM runs or they can be accessed independently. By default, the meshing tools are not run automatically after the point cloud(s) is created. You can set whether the meshing tools run on Preferences - Dense Surface.
Besides converting point clouds to meshes, the meshing tools will also fill holes, smooth the data etc.. In addition, there are tools for editing/deleting individual points, for flipping the normals, and for loading and saving meshes from/to disk.