It is a one way or unidirectional communication between two devices in which one device is sender and other one is receiver. Devices use the entire capacity of the link to transmit the data. It is like a one way street where vehicles can move in only one direction. For example, data entered through a keyboard or audio sent to a speaker are one way communications.
With the advent of IoT, controlling home appliances is another example of simplex communication as shown in the Figure. One can control fans, lights, fridge, oven etc. while sitting in the office or driving a car.
Simplex communication
