The McGurk Effect is a perceptual phenomenon that demonstrates how visual information can influence what we hear. When a person hears a sound while simultaneously seeing a video of someone articulating a different sound, the brain may combine the two inputs, leading to a third perception. For example, if the audio says "ba" but the lips are seen saying "ga," the listener might perceive "da." This effect highlights the importance of multisensory integration in human communication. It shows that our understanding of speech is not solely based on auditory input but is also significantly shaped by visual cues, such as the movements of the mouth and face.