A technology that sensed the availability and receptivity of a user to receive a communication. Presence is usually accompanied with IM (Instant Messaging) and is becoming more common because of the introduction of Microsoft’s Live Communications Server. "Presence" detects when a user is available just like the "buddy lists" that are used in consumer IM applications. Based on a personal profile, "Presence" determines whether the user is willing and able to receive messages immediately (and in which message format) or whether to store the messages for future retrieval.