Certain text blocks support rich text markup. These are tags which modify the appearance of the text for example bold, italics, colors, etc.
Which tags are supported depends on the doc_glazier mode being used. Most players will be using the default, uGUI.
These tags are specific to Unturned.
<br>: New line. Supported in most multi-line text boxes such as dialogue, signs/notes, item descriptions, etc.
<name_npc>: Insert the NPC character's name. Only supported in NPC dialogue.
<name_char>: Insert the player character's name. Only supported in NPC dialogue and signs/notes.
<pause>: Pause dialogue for 0.5 seconds before continuing. Only supported in NPC dialogue.
For the full list of tags please refer to the TextMesh Pro documentation here: https://docs.unity3d.com/Packages/com.unity.textmeshpro@2.2/manual/RichText.html
For the full list of tags please refer to the Unity styled text documentation here: https://docs.unity3d.com/2018.3/Documentation/Manual/StyledText.html