Sound waves are a fundamental aspect of physics, representing mechanical vibrations that travel through a medium. Unlike electromagnetic waves, which can propagate through the vacuum of space, sound waves require a material medium such as air, water, or solid substances. These waves are generated when an object vibrates, causing nearby particles in the medium to oscillate. As these particles move back and forth, they transfer energy to adjacent particles, creating a propagating wave of compression and rarefaction. This process continues outward from the source, allowing sound to travel over distances.

The two primary types of waves in physics are transverse and longitudinal waves. Sound waves fall into the category of longitudinal waves, meaning that the oscillations of the particles occur parallel to the direction of wave propagation. In contrast, transverse waves, such as water waves and electromagnetic waves, involve oscillations perpendicular to their direction of movement. In a sound wave, regions of compression correspond to areas where particles are densely packed together, while regions of rarefaction represent areas where the particles are spread apart. This alternating pattern of compression and rarefaction allows the wave to carry energy without transporting matter itself.