Acoustic pressure refers to the local pressure variation from the ambient atmospheric pressure caused by sound waves. It is a measure of how much the pressure fluctuates as sound travels through a medium, such as air or water. This pressure variation is typically expressed in pascals (Pa) and is crucial for understanding how sound interacts with different environments. In acoustics, sound waves create regions of compression and rarefaction, leading to changes in pressure. The intensity of the sound is related to the amplitude of these pressure variations. Higher acoustic pressure indicates louder sounds, while lower pressure corresponds to quieter sounds.