Data signal is a method of how information is transferred. usually it is transferred in binary code in signals or pulses and may be contained in a packet.
A composite signal is a mux or a bus signal. These can be thought of as a collection of other component signals.
In telecommunications and computing, bit rate (bitrate or as a variable R) is the number of bits that are conveyed or processed per unit of time.
Throughput refers to how much data can be transferred from one location to another in a given amount of time. It is used to measure the performance of hard drives and RAM, as well as Internet and network connections.
A wavelength is a measure of distance between two identical peaks (high points) or troughs (low points) in a wave .
At best the signals propagate (radiate) through free space at the speed of lignt (3*10**8 m/s). In contrast, the speed of propagation through twisted pair wire or coax is 2/3 of this value.