Simplex, Half duplex, and Full duplex

1. Overview

2. Description

2.1 Simplex

It's like a one-way street. 

2.1.1 Usages

garage door opener, baby monitor, wireless microphone, car key fob, Radio, TV station.

2.2 Half Duplex

Half Duplex transmission is when signals travel in both directions, but one at a time. Both transmitter and receiver can send signals, but they must take turns.

2.2.1 Usages

Walkie-talkie

2.3 Full Duplex

Full Duplex is two-way communications and signals travel in both directions simultaneously.

2.3.1 Usages

Telephone call.

3. Reference

https://www.youtube.com/watch?v=kKCDLk9irkQ