"Piano forte" (see the Webster 1913 definition of piano) was the early term for the rudimentary pianos which took the harpsichord's place in traditional classical music. Piano forte literally translates to "soft-loud", which referred to the fact that the volume of notes played on a piano could be adjusted, unlike the uniform strength of a harpsichord. (Piano and forte are abbreviated p. and f., respectively, in sheet music.)

The piano's insides include dampers, which allow the volume of a tone to be diminished or increased. This is made possible by the hammer-and-string design. A harpsichord uses a plectrum to actually pluck the string when the appropriate key is pressed. As a result of this improved control, the harpsichord is now rarely seen in orchestral performance.

The first piano forte was created by Bartolomeo Cristofori, who called it a gravicembalo col pian e forte (literally: "harpsichord with soft and loud"), in 1709. Several were commissioned for the kings of Germany and Austria-Hungary, from where they spread to Britain, America, and the rest of the civilized world. By 1815 the piano had rendered the harpsichord effectively obsolete, although it is occasionally still used today. The book Gödel, Escher, Bach: An Eternal Golden Braid goes into this subject in great detail, and is highly recommended reading.