Here's why:

* Intensity refers to the power of sound waves per unit area.

* Watts (W) represent the power, which is the rate at which energy is transferred.

* Square meters (m²) represents the area over which the sound waves are spread.

While W/m² is the standard unit, you may also encounter other units for sound intensity, like:

* Decibels (dB): This is a logarithmic scale that compares the intensity of a sound to a reference level. It's more commonly used to describe loudness perception.

* Sound Pressure Level (SPL): Measured in pascals (Pa) or decibels (dB), it represents the amplitude of the sound wave.

Let me know if you'd like to explore the relationship between these units or have any other questions!