Deceptive cadence

In Western musical theory a cadence (Latin cadentia, "a falling") is a particular series of intervals or chords that ends a phrase, section, or piece of music. Cadences give phrases a distinctive ending, that can, for example, indicate to the listener whether the piece is to be continued or concluded. An analogy can be made with punctuation, with some weaker cadences acting as commas, indicating a pause or momentary rest, while a stronger cadence will then act as the period, indicating the end of the phrase or musical sentence. Cadences are called "weak" or "strong" the more or less final the sensation they create. It should be noted that while cadences are usually classified by specific chord or melodic progressions, the use of such a progression does not necessarily constitute a cadence — there must be a sense of closure, as at the end of a phrase.  Harmonic rhythm plays an important part in determining where a cadence occurs.
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