A mach wave is an aerodynamic phenomenon that occurs when an object travels faster than the speed of sound. It is often referred to as a shock wave because of the sudden change in pressure and temperature that results from the air being compressed by the object's passage. Other synonyms for mach wave include shock wave, sonic boom, sound barrier, and supersonic wave. These terms are often used interchangeably, although they may have slightly different connotations depending on the context. For example, a sonic boom is specifically the sound heard when a mach wave passes overhead, while the sound barrier refers to the theoretical limit of how fast an object can travel through the air.