Music has often been compared with language itself, and the comparison is quite legitimate. While it combines easily with actual language, it also speaks a language of its own, which it has become a platitude to call universal. To understand the significance of the organizing factors of rhythm, melody, harmony, tone color and form, the analogy of a familiar language is helpful. Music has its own alphabet of only seven letters, as compared with the twenty-six of the English alphabet. Each of these letters represents a note, and just as certain letters are complete words in themselves, so certain notes may stand alone, with the force of a whole word. Generally, however, a note of music implies a certain harmony, and in most modern music the notes take the form of actual chords. So it may be said that a chord in music is analogous to a word in language. Several words form a phrase, and several phrases a complete sentence, and the same thing is true in music. Measured music corresponds to poetry, while the old unmeasured plain-song might be compared with prose.