I always thought that a mesh is just the 3D-data of an object (the vertex-data and triangle-data which make up a model, thus the model itself), while an entity is basically the same, but with added data about it's position and rotation in the 3D-world.
So when you load a 3D-model into a 3D-world, it transforms itself into an entity, because it automatically gets data assigned to it about it's position and rotation in the 3D-world.
I think this can be correct, because when you load a 3D-model, you use LoadMesh (or LoadAnimMesh), which only holds data about the 3D-model, but when imported into the world, you position it with PositionEntity, so your mesh becomes an entity after importing.
So when you load a 3D-model into a 3D-world, it transforms itself into an entity, because it automatically gets data assigned to it about it's position and rotation in the 3D-world.
I think this can be correct, because when you load a 3D-model, you use LoadMesh (or LoadAnimMesh), which only holds data about the 3D-model, but when imported into the world, you position it with PositionEntity, so your mesh becomes an entity after importing.