Abstract
This article examines two components of temporality that have implications for electronically mediated communication. One is the dichotomy of simultaneous/non-simultaneous communication and then the varying degrees of non-simultaneity that are possible. The other is the fundamental difference between timed and untimed communication. Timed communication is temporally based and sequential, while untimed communication, such as print and still image content, is spatially based. The article argues that there are two fundamental types of mediated communication: communication mediated across time and communication mediated across space. The implications of temporality for both forms of mediated communication are examined in detail. The implications of temporality and mediated communication for multimedia, technology convergence, and research are discussed.