The first real piano was a harpsichord with small hammers, invented by Bartolomeo Cristofori (1655-1731), an Italian maker of harpsichords from Florence, around 1700. By adding different groups of strings to the harpsichord, Cristofori was able to extend the range of the harpsichord. But it wasn't until he made small hammers that struck the strings rather than plucking them that a real breakthrough came about. Now a player could control the sound of each note by the force with which he struck the key, accenting the notes. By doing so, he was able to make the whole range from piano (soft) to forte (loud) to draw from for music.
Cristofori called his new invention, "gravicembalo coi piano e forte," which meant ‘harpsichord with soft and loud.' Thankfully, this name was later reduced to piano forte and finally, simply piano.
Cristofori's new invention, however, did not catch the public's imagination and he soon returned to making harpsichords. It was up to others to refine the piano that we know today in the next 100 or so years. In fact, in 1777, the first public piano performance was given by Johann Christian Bach, son of the great Johann Sebastian Bach.
Playing piano became popular once such composers as Austrian composer Wolfgang Amadeus Mozart wrote his first piano concerto at age 11 which he played on a piano made by skilled German piano maker Johann A. Stein. Along with Ludwig Van Beethoven, Mozart created music specifically for the piano that demanded the best from both performer and instrument. Beethoven was known to attack the piano with such force that piano keys and piano strings were liable to go flying.
As pianists demanded more and more from their pianos, manufacturers built larger and heavier frames to support the higher string tension that was desired. The one piece cast iron frame, developed in 1825, was a great advancement. By 1880, the piano had developed into the acoustic piano we know today.
With the digital age and computers in the last decade, digital pianos and keyboards have given new life to the popularity of learning to play piano.