Wave refraction is the bending of waves as they approach shallow water or obstacles. This phenomenon occurs because different parts of a wave travel at different speeds when they enter shallower areas. The part of the wave that reaches the shallow water first slows down, while the deeper part continues moving faster, causing the wave to change direction. As a result of wave refraction, waves can become concentrated on certain areas of a shoreline, leading to increased erosion or sediment deposition. This process is important for coastal processes and can affect the formation of features like beaches, sandbars, and estuaries.