We used to call those signs in the following names :
Popular style, and the surface is flat with fabricated edges, can be added lights and painted .
3D signs: the surface is prismatic , man-made, expensive
Can add lights and painted.
Flat cut (Solid letters) : thinkness from 1 mm, can be sticked on glass, wall ,door etc
By knowing this knowledge, you will know what exactly suits for you.