To transmit messages in secret.
gears are used to transmit power and motion
micro wave rays.
It can be used to transmit important messages from the top of an organisation to the lower levels.
It can be used to transmit important messages from the top of an organisation to the lower levels.
Infrared waves transmit heat energy. They are commonly used in applications such as remote controls, night vision devices, and infrared heating systems.
Electromagnetic waves are used in communication to carry information through the air or space. They transmit signals between devices like radios, cell phones, and satellites, allowing for the exchange of data and messages over long distances.
A transmitter is a set of equipment used to generate and transmit. It transmits electromagnetic waves carrying messages or signals.
Electrical energy is used to transmit messages from one part of the body to another through the nervous system. Nerve cells called neurons use electrical signals to communicate with each other and relay information throughout the body.
Class D
Cellular networks are systems that allow mobile devices to communicate with each other by connecting to a network of cell towers. These networks enable phone calls, text messages, and internet access on mobile devices by using radio waves to transmit information. Various technologies, such as 3G, 4G, and 5G, are used to provide different levels of speed and coverage.
I think it used only light to transmit messages instead of electricity... I could be wrong though you may want to try wikipedia