FE geometry is topology on top of mesh, meaning CAD and mesh exist as a single entity. The purpose of FE geometry
is to add vertices, edges, surfaces, and solids on FE models which have no CAD geometry.
1D mesh that allows accurate testing of connectors, such as bolts, and similar rod-like or bar-like objects that can
be modeled as a simple line for FEA purposes.
Volume mesh or "solid meshing" uses three-dimensional elements to represent fully 3D objects, such as solid parts
or sheets of material that have enough thickness and surface variety that solid meshing makes more sense than 2D shell
meshing.