In the early 18th century, the term "symphony" was applied to any instrumental prelude, interlude, or postlude. In modern usage, the term is applied to a large composition for orchestra, generally in three or four movements. The symphony may also be defined as a sonata for orchestra. The earlier symphonies, those of the Classical era, were generally simpler, and of a smaller scale. By the late Romantic era, the symphony had grown in number of movements, length of movements, number of instruments, variety of instruments, and dynamic range. The speed of the rhythm of a composition. Tempo is measured according to beats per minute. A very fast tempo, prestissimo, has between 200 and 208 beats per minute, presto has 168 to 200 beats per minute, allegro has between 120 and 168 beats per minute, moderato has 108 to 120 beats per minute, andante has 76 to 108, adagio has 66 to 76, larghetto has 60 to 66, and largo, the slowest tempo, has 40 to 60.