multiplexing The transmission of several channels of information over a single channel without interference and the subsequent recording of that information on magnetic tape. The digital data recorded are in the order: channel 1, sample 1; channel 2, sample 1; … channel n, sample 1; channel 1, sample 2; channel 2, sample 2; … channel n, sample 2; etc., which is a very efficient way to record information on magnetic tape. Demultiplexing is the process by which the tape is made readable by a computer and its data are made available for processing.

multiplexing The process of combining multiple messages simultaneously on the same physical or logical transmission medium. There are two main types: time division multiplexing (TDM) and frequency division multiplexing (FDM). In TDM a device is allocated specific time slots in which to use the transmission medium. FDM divides the transmission medium into channels of smaller bandwidth to which the user has exclusive rights. FDM and TDM can be combined to provide devices with time slots of logical channels.