 Categorical perception is the experience of perceiving phenomena that can be varied along a continuum as fixed tokens. Since the speech signal presents us with far more information than we need in order to recognize what is being said, the central idea is that the speech perception mechanism is especially sensitive to specific cues in the speech signal. These cues are not perceived along a continuum but as fixed categories. Let us take voice onset time to illustrate this phenomenon. The voice onset time or short VOT is the point when vocal fold vibration starts relative to the release of a closure. It is crucial for us to discriminate between clusters such as Ba and Pa where we know that a grand deal delay of VOT does not lead to a differentiation between voiceless and voiced consonants. Let us illustrate this. As we heard, a VOT value of around 30 milliseconds serves as the key factor. In other words, if VOT is longer than 30 milliseconds, we hear Ba. If VOT is shorter, the perceptual result is Pa. Other perceptual categories relate to the origin of the second formant that allow us to distinguish between different places of articulation or frequency patterns that help us to identify a larger number of speech sounds. Categorical perception is thus opposed to continuous perception where sensory phenomena are not based on fixed tokens but can be located on a smooth continuum.