Let's Chat

So what happens when I start the IM program?
Your computer logs in to the server to let it know that you’re online and tells the server your computer's IP address, which will be important in a minute. The server then does two things. First, it lets all your friends know you’re online. The server sends a message to all your friends' computers to let them know this. Then the server sends a message to your computer that tells you which of your friends are online. It also tells your computer the IP addresses of all of their computers.

What happens when I actually want to send a message – say to my friend “HappyCat123”?
You click on that name and start typing your message. When you press "Send,” your computer looks up the IP address for HappyCat123 and sends the message straight to her computer. Her IM program gets the message and displays it. Then she might send a reply. Your two computers are talking directly to each other through the Internet.

You mention something called an IP address – what is that?
It’s sort of like your street address. On the Internet, every computer has a unique IP address, which might look like this: 154.87.632.90. The IP address of every machine on the Internet is different. So, if the server sends your machine the IP address of your friend's machine, and if the server sends your friend's machine the IP address of your machine, then your machine and your friend's machine can talk directly to each other. That’s basically what makes "instant messaging" so instant! Now, when you send a message, it goes directly from your computer to your friend's computer. There’s nothing in between to slow things down; your message is moving at the speed of light, just like a phone call. When you talk on the phone, your voice reaches your friend's ear in a few milliseconds. Your instant message moves at the same speed.

But what if I want to send a message to 10 of my friends at the same time?
Your machine knows the IP addresses of all 10 of your friends' machines. So it sends 10 messages, one right after the other, to 10 different IP addresses.

What happens when I’m finished IM’ing for the day?
When you’re done, you close your IM program. Or you turn off your machine. A message goes to the server that tells it you are logging off. So the server sends a message to all your friends to say that you’re gone. Now they won't send messages to your machine any more, until you log in again.

IM Code for Beginners
aaf = as a friend	afc = away from computer
ayt = are you there?	b4n = bye for now
brb = be right back	cmc = call my cell
ctn = can't talk now	cd8 or cd9 = parents are around
g2g = got to go	idk = i don't know
mirl = let's meet in real life	nmu = not much, you?
p911 = parent emergency	plox = please
ttfn = ta ta for now	tffw = too funny for words
ur2gr8 = you are too great	wu = what's up?