| What Is... | Sharing an IMV |
An IMVironment (IMV) is a themed environment that you can choose to show in the conversation area of your conversation window while instant messaging a contact. The contact sees the same IMV and has the option of turning it off or selecting a different IMV to share with you. Each time you instant message this contact, the same IMV displays in your conversation window until you change it or turn it off.
Many IMVs are animated, such as Fishtank, which includes swimming fish, and Falling Hearts, which includes hearts floating down from above. Your instant messages display over the top of these IMVs.

Several IMVs are interactive, such as Doodle, which lets you and your contact draw on the same canvas.
Notes:
IMVironments work only on PCs.
IMVironments aren’t available when you converse with contacts
outside the Yahoo! network, such as your Windows Live™ Messenger contacts and your Pingbox™ visitors.
To use an IMVironment, your PC must have the following: