A three -phase electricity system.
The address 136 is active and the electric motor works because all the lines of this address are active.
Induction sensors associated with relays exclude electric motors with partly active lines.
This example shows radio technology.
On the left we have 4 transmitters and each has its own frequency that it transmits.
On the right we have 6 receivers, and each receives only a particular, unique combination
of 2 frequencies.
The dashed wavy lines represent radio waves from transmitter to receiver.
To transmit the radio waves, the space is used as "lines".