The property of waves that allows them to bend around a barrier is diffraction. Diffraction is the spreading out of waves as they pass through an aperture or around an obstacle. It is a common phenomenon that occurs with all types of waves, including light, sound, and water waves.

The amount of diffraction that occurs depends on the wavelength of the wave and the size of the obstacle. Shorter wavelengths diffract more than longer wavelengths, and smaller obstacles cause more diffraction than larger obstacles.

Diffraction is responsible for a number of everyday phenomena, such as the ability to see around corners and the formation of shadows. It is also used in a variety of applications, such as microscopy, holography, and X-ray imaging.

Here is a more detailed explanation of how diffraction works. When a wave encounters an obstacle, it spreads out in all directions. This spreading out is due to the fact that the wavefronts of the wave are no longer parallel to each other. Instead, they are curved, with the curvature increasing as the wave gets closer to the obstacle.

The amount of spreading out that occurs depends on the wavelength of the wave and the size of the obstacle. Shorter wavelengths diffract more than longer wavelengths, and smaller obstacles cause more diffraction than larger obstacles.

Diffraction is a fundamental property of waves. It is a consequence of the fact that waves are not simply particles, but are also disturbances that spread out in space.