How to Communicate Your Online Status with the Mac Messages App
Want to find out if your buddy is able to chat? With Mac iMessages, you’ll mostly be able to tell whether your buddies are online at the moment and willing to give you the time of day. Here’s how:
A green circle to the left of a person’s name means that he or she is ready and (presumably) willing to talk.
A red circle means that the person is online but otherwise engaged. The person is considered to be Away.
A yellow circle means that the person is idle and hasn’t used the machine for a while. (The window tells you how long the person has been in this state.) Your buddy just hasn’t bothered to change his or her status from Available to Away.
If a name is dimmed, your buddy is offline.
You can set your own status for everyone else to see, and you aren’t limited to Available or Away. Click below your own name and choose Custom from the contextual menu. You can choose a custom message to appear next to a green or red circle, depending on your particular set of circumstances. Type any message you want, like Can chat in a pinch but busy or Back after lunch.
Incidentally, if you’ve been absent from the computer for a while, the Mac kindly welcomes you back to the machine and asks whether you want to change your chat status from Away back to Available.
iMessage doesn’t actually use detailed online statuses like, say, AIM, in which you can indicate that you’re out to lunch, in a meeting, or otherwise unavailable. (You can still establish online statuses for the IM programs you use within Messages.)
So if you want to stop receiving iMessages on a temporary basis on your Mac (while still receiving messages on your iOS devices), you have to disable iMessage on your Mac. In Messages Preferences, click Accounts, and select or deselect the Enable This Account check box.