Data signals can be sent over a network cable in one of two ways: broadband or baseband. One good example of broadband signaling would be how you view different channels through your cable box and a signal coaxial cable carrying multiple signals in cable television.
Whereas, baseband signaling only sends a single signal over the cable. This type of signaling is typically used in Ethernet networks, with the exception of 10Broad3 standard (rarely used). Baseband uses very simple transceiver devices that send and receive signals on a cable. The simplicity behind baseband signaling is that only three states need to be distinquished: one, zero and idle. Broadband transceivers are much more complex because they must be able to distinquish those same states, but on multiple channels within the same cable. Because of its simplicity, baseband signaling is used on most Ethernet networks.