Reflection is the chynge in direction o a wavefront at an interface atween twa different media sae that the wavefront returns intae the medium frae which it originatit. Common examples include the reflection o licht, soond an watter waves. The law o reflection says that for specular reflection the angle at which the wave is incident on the surface equals the angle at which it is reflected. Mirrors exhibit specular reflection. In acoustics, reflection causes echoes an is uised in sonar. In geology, it is important in the study o seismic waves. Reflection is observed wi surface waves in bodies o watter. Reflection is observed wi mony types o electromagnetic wave, besides veesible licht. Reflection o VHF an heicher frequencies is important for radio transmission an for radar. Even haird X-rays an gamma rays can be reflectit at shallae angles wi special "grazin" mirrors.