Why are some usernames gray?

I’ve noticed a few users (usually new ones? But that may be confirmation bias) who have a gray username instead of the default black font. What does this mean, exactly?

I can’t say I’ve ever noticed this … except for quotes. My quote from your post will show your name greyed. Is that what you mean?

If not, can you link to a few examples?

No, I mean their name in the main thread; see the OP here:

Could it be a novitiate user who hasn’t yet gotten the right number of points or badges or posts or whatever to ascend to the next Level?

ETA: Discussion of Discourse Trust Levels here.

I noticed the same thing and guessed it was new users at the lowest trust level.

Here it mentions that new users with trust level 0 have a lighter grey username:

https://what.thedailywtf.com/topic/11708/user-trust-levels

That makes sense, thanks!

Yes, these light grey names indicate new users at trust level 0 – but I suggest referring to the official docs:

The first post by a user will be called out in a way that is only visible to higher trust users, as well. Idea being “hey, newbie here, let’s take extra care”.

(We also do this for posts from users who have been absent for a long time.)