@YoloMcSwaggins123 (View Post)
Blue signs are "save links" and clicking them takes to another save:

{c:111111|Wow! I'm a save link?}

Yellow-ish signs are "Thread links" and clicking them takes to a forum thread:

{t:18053|Link to this thread!}

Yellower signs are "Spark signs" and clicking them produces a spark :

{b|SPARK THIS OR ELSE}

Temperature signs are just live-updating:

{t}

So are pressure signs:

{p}