A fortepiano, sometimes referred to as a pianoforte, is an early piano. In principle, the word "fortepiano" can designate any piano dating from the invention of the instrument by Bartolomeo Cristofori in 1698 up to the early 19th century.

Starting in Beethoven's time, the fortepiano began a period of steady evolution, culminating in the late 19th century with the modern grand. The earlier fortepiano became obsolete and was absent from the musical scene for many decades. In the 20th century the fortepiano was revived, following the rise of interest in historically informed performance.

"Fortepiano" is Italian for "loud-soft", just as the formal name for the modern piano, "pianoforte", is "soft-loud".

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