Edge in 5 francs k 1831 Louis Philippe [gelöst]

What is the difference between hollow edge and engraved edge
and to notice itThanks for any respod

there are two types of letters of "dieu protege la france"
raised, 'en relief' like the lettering on the face of the coin,
or incused, 'en creux' that is, stamped into the surface.

hollow and engraved both mean the same thing to me, where ever you read that should be adjusted.

Thanks alot