Unified Messaging (or UM) is the integration of different streams of communication (E-mail, Voice, Fax.) into a single unified message store, accessible from a variety of different devices.

While traditional communications systems delivered messages into several different types of stores—voice mail systems, e-mail servers, and stand-alone fax machines—with Unified Messaging all types of messages are stored in one system. Voice mail messages, for example, are delivered directly into your in box. You see them right beside your e-mail when you open up Microsoft Outlook, offering powerful new ways to collaborate more effectively. For example, you can forward a voice mail or fax. You can even take notes in your voice mail message or search for old voice mail messages.