The Reflection Coefficient is a measure used in physics and engineering to describe how much of a wave is reflected by an interface between two different media. It is defined as the ratio of the amplitude of the reflected wave to the amplitude of the incident wave. This coefficient helps in understanding how waves, such as sound or electromagnetic waves, behave when they encounter changes in material properties. In practical applications, the reflection coefficient is important in fields like telecommunications and acoustics. For example, in telecommunications, it helps engineers design better antennas by minimizing signal loss. In acoustics, it aids in optimizing soundproofing materials to reduce unwanted noise reflections.