When typing an iMessage from a Mac or other non iPhone device how do you get a subject field?

Question

From the iPhone there is now an option to add a subject field to your iMessages.  This can be nice but what about doing it from the MAC or other device.  Also how do you insert a line break (which I'm told is alt/option enter) from an iPhone.  Sorry two questions in one.

Answer 1

Hi,
The Messages app on the Mac has no means of indicating a "title" or subject matter.
It only sends messages be they iMessages to Contacts or IM (instant Messages) to Buddies on various services that you could join.
Re 1) The AIM service added the ability to use the "/me" lead in/pre-emptive text which adds the little grey center info text to AIM chats as my pics show.
In other services that do not support "/me" you see a sentence that starts "/me".
On the iPhone as an  iMessages item it appears like this
They appear as Sent items due to the Sync process.
Re 2)  No.
I am just suggesting using a feature that works in the Messages (and the previous iChat) App using an AIM Account in Messages (as it appears to work at your end all the time in any account) so that you can create something that can be used as a "subject" marker.
re 3) Yes.
The original premise was you sent something like "/me waves" which appears like the time stamps as "Your Name waves"  (Your Name on the other depends on what they have in their Address Book or Contacts app as your details (you could appear as just a Buddy ID of some sort.)
Enlarging part of that earlier pic.
The so called Subject one.
Grammatically it could do with a 'has".
Re 4.
AOL (who Own AOL Instant Messenger)  gave out AIM names with AOL accounts  and with accounts with other companies that they owned.
At one time they owned Netscape  Mostly Netscape referred to a Browser that was popular on the Mac at the time.  It had a Messenger part added to what it could do and registration gave you an AIM ID (Screen Name)
This tended to be the Username part of your your account name which was an email.
We are talking when there were computers sold by Apple that could boot into OS 9 as easily as they did into OS 10.2.
iChat 2 that did the first Video chats was in OS X 10.3
At that point iChat was an AIM only client.  This continued until iChat 3 which added Jabber (and that version required a small amount of work to add a GoogleTalk ID)
Basically when I bought the G4 Tower listed below I already had an AIM name by preferring to use Netscape over Internet Explorer.
At various points I have tried ProteusX  (the Original Site seems to have gone now).
I have also tried AdiumX
Both these were and are text only multiple service apps.
I have used Psi  This is a Jabber only app.  It is a bit "windowsy" as it is a cross platform app written in Java (means you have to download and Install Java and keep it updated)
I got it for doing this http://allforces.com/2005/05/06/ichat-to-msn-through-jabber/
These instructions need you to be able to "register" for Transport on Jabber servers which then allows you to link to your MSN or other service account to in turn add those Buddies to your Jabber Buddy List.
I have tended to Stick with using my AIM name as my main form in iChat and Messages because it has the Privacy and Security settings that allow you to Block people, or have Allow Specific people or Allow Buddy List only people as ways of restricting who can see when you are on Line.
AIM also works with Apple IDs ending with @mac.com and iCloud linked @me.com and @icloud.com  (Lapsed @me.com from MobileMe will not work)
You have to keep the password to 16 characters or less to work with the AIM servers.
There is also MeBeam  which has been known as Koowy  (coo-we) for a while and currently seems to promote itself as "CuSeeMe.tv"
It as a site you will need Flash for.
It then, when you allow it, has access to your Camera and Microphone and you can video to people in "rooms" (private URL) you create.
I have tried Skype in it's early days.
It shares your connection to the internet to make lots of connections to maintain a non centralised service.
This makes it vunerable to "Man-in-the-Middle" attacks becasue at time you are the man in the middle.
Each download used to list it's own Specified port to use but if you didn't set it it used port 80 (web Browsing or port 110 (mostly mail) to connect.  Some see this as defeating your firewall or router as it is not made clear in the set up.
I have Office 2004, and 2008 and whatever the last one for Macs was called. (2011 I see on the box)
This has MSN Messenger which I have tried but don't like  (Microsoft do some great Apple apps in the Office collection but MSN is not one of the).
Yahoo has been in some variant of Beta 3 for almost as long as the OS has been OS X  (it is certainly about 8 years).
It never seems to get to a first GM release.
This can do "video" but broadcasts this to anyone and the Audio is then to one Buddy.
Basically iChat was the app I used first and an AIM name I already had.
Over the years I have created several Apple ID (some during a time when @mac.com name could be registered as "iChat Names"  after the .Mac service had finished).
AIM have always been there.
Google has been there some of the way.
(Other jabber servers can come and go)
I do have my Yahoo account set up in Messages but it basically was as a test and I rarely use it  (it is only text and does not  do Video in the iChat 6 or Messages apps).
I am not a great phone user so iMessaging people is limited for me.
(I know about 2 people who I could iMessage outside of my family).
10:57 pm      Saturday; March 15, 2014
​  iMac 2.5Ghz i5 2011 (Mavericks 10.9)
 G4/1GhzDual MDD (Leopard 10.5.8)
 MacBookPro 2Gb (Snow Leopard 10.6.8)
 Mac OS X (10.6.8),
 Couple of iPhones and an iPad