| Messaging a Contact | Messaging Multiple Contacts | Using Smart Tags | Forwarding IMs to Your Mobile | Saving an IM Conversation to a Text File |
Instant messaging is the ability to converse through textual messages in real time with other people over the Internet. Similar to email, instant messages consist of text that you and your contacts send back and forth. But, unlike email, you don’t have to wait hours or days for an answer. As the name suggests, messages usually arrive instantly.
You can send instant messages to contacts in your Messenger List or to anyone else if you know their Yahoo! ID or their Windows Live™ ID. You can even instant message Pingbox™ visitors. To learn more, take a look at Chatting With Visitors to Your Personal Web Page.
The conversation window (shown below) is where you type, send, and receive instant messages.

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Open a conversation window with the name of the person you want to instant message.
If the name is in your Messenger List, double-click the name.

If the person isn’t in your Messenger List, type the person’s full Yahoo! ID or Windows Live™ ID in the Contact Action Bar above your List, then double-click the name when it displays below the bar.

Tips:
Some IDs have domains other than @yahoo.com,
such as @sbcglobal.net, @verizon.net,
or @msn.com. When typing these IDs, be sure to add
the full domain (person1@sbcglobal.net, person2@verizon.net, person3@msn.com).
You don’t need to type the @yahoo.com domain.
Don’t forget to use the Contact Action Bar if you have
a long list of names. As you type, Messenger displays possible matches
below the bar. Just double-click the name of the contact you want
to instant message.
A conversation window opens.
In the input area of the conversation window, type your message, then press the Enter key on your keyboard or click the Send button.

The conversation area of the window shows your message and your contact’s replies.

Consider adding people to your Messenger List so that you can easily communicate with them whenever you like. See the Adding Contacts to Your Messenger List tutorial for more information.