In Dark Souls 3 (and some of the previous games in the series, if I remember correctly), messages on the ground have a "medallion" to the left of the message text, as pictured below:
The majority of messages I see in-game have the style of medallion shown in the picture above, but I have seen a few that are gold or blue, and have different designs on them. I know the "bell" design signifies that the message is a "system" message (i.e. a message that was hard-coded into the game), but I'm not sure about any of the others.
Does anyone know what the different medallion colors/designs mean? My google-fu is normally pretty strong, but it has failed me when it comes to answering this question.