The bending of a wave around a barrier is called diffraction.
Diffraction occurs when a wave encounters an obstacle or a slit that is comparable in size to its wavelength. As the wave passes around the barrier or through the slit, it spreads out and bends around the edges. This phenomenon is a key characteristic of wave behavior and is observed in various types of waves, including sound waves, light waves, and water waves.
For example, when light passes through a narrow slit, it diffracts and creates a pattern of bright and dark fringes on a screen placed behind the slit. Similarly, sound waves can diffract around corners, allowing you to hear sounds even when the source is not directly visible.
In summary, diffraction is the process by which waves bend around obstacles or spread out after passing through narrow openings, and it is a fundamental concept in the study of wave optics and acoustics.