Instant Messaging: Send text messages in real-time to your friends on Yahoo! Messenger.
Chat Rooms: Join a chat room to meet new friends while you discuss your favorite topics.
Photo Sharing: Share photos from your desktop or Flickr, then discuss them over IM while you and a friend view them together.
PC-to-PC Calls: Make a voice call to another Yahoo! Messenger user for free (microphone and speakers/headset required).
Phone Out (PC-to-Phone Calls): Call friends on their regular or mobile phones from Messenger for as low as 1˘ a minute (Phone Out account required).
Phone In (Get a Phone Number for Messenger): Get a new phone number that allows you to receive calls in Yahoo! Messenger (Phone In account required).
SMS (Text Messaging): Send text messages from Messenger to your friends mobile phones for free.
Webcam: Plug in your webcam to share live video with your friends on Yahoo! Messenger.
IM Conferencing: Instant message with many friends at once in a conference room (includes voice capabilities, where available).
IM with Friends on Other Networks: IM with friends who use Windows Live™ Messenger, Reuters Messaging, and Lotus Sametime — right from Yahoo! Messenger.
File Transfer: Send files instantly to a friend while you IM (2 GB limit).
IM Forwarding to Mobile: When you sign out of Messenger, have new IMs sent to your phone as text messages.
Contact Search Bar: Quickly find a contact to IM, call, SMS or more.
Yahoo! Search: Start a web search right from your Yahoo! Messenger window.
Yahoo! Address Book: View and edit your Yahoo! Address Book information for your contacts right from Messenger.
Stealth/Privacy Settings: Make yourself appear online to some friends, and offline to others.
Call Forwarding: Have incoming calls to Messenger forwarded to another phone number, even if you're signed out (Phone Out account required).
Yahoo! Mail alerts: Get notified when new a new Yahoo! Mail message arrives.
Voicemail: When friends call you on Yahoo! Messenger, they can leave you a voicemail if you're unavailable.
Message Archiving: Maintain a private archive of your IM conversations.
Tabbed IM Windows: Reduce desktop clutter by organizing multiple conversations into a single window.
Buzz Alert: Get your friend's attention with a click of the Buzz button.
Yahoo! Updates: Get real-time updates in Yahoo! Messenger about what your friends are posting online, reviewing and generally buzzing about
Plug-ins: Add content, services and games to Messenger that you can enjoy on your own, or with friends while you IM.
Audibles: Send an animated, talking character to a friend to liven up your IM conversation.
Emoticons: Express your feelings with these animated, smiling faces.
Avatars: Represent yourself with a stylized, graphic image where you can choose the hair, clothing and more.
Display Images: Display an image to represent yourself to your friends.
Skins: Choose a different skin to give your IM world a new look.
IMVironments: Liven things up with interactive, themed backgrounds in the IM window.
Yahoo! Games: Play a game of pool, backgammon, checkers and more with a friend while you IM.
Custom Status Messages: Tell your friends what you're doing, seeing or feeling by customizing your online status message.
Custom Ringtones: Assign ringtones to different callers, or upload your own audio files to use.
Customizable Fonts & Colors: IM with a font, color and style that suits your personality.
Sound Effects & Soundtrack (During Voice Calls): Throw a sound effect in while you're on a call or upload a music file to play as a soundtrack in the background.
1. Instant message with one friend, or conference in a bunch
2. All-new Insider with Yahoo! Mail, news, weather, search and more
3. Easily find or invite friends from other services to come chat with you
4. Send text messages (SMS) to friends' mobile phones for free*
5. Make free PC-to-PC calls and PC-to-phone calls for as low as 1˘ a minute (plus free voicemail!)
6. Use the built-in media player to watch web videos and view photos with friends
7. Show your style with emoticons, Avatars, audibles and IMVironments