Short answers, pulled from the story.
The earliest known keyboard instrument is the Ancient Greek hydraulis, a type of pipe organ invented in the third century BC. It remained the only keyboard instrument until the fourteenth century, when the clavicymbalum, clavichord, and harpsichord appeared.
Bartolomeo Cristofori introduced the first template for the modern piano in 1698 in Italy, calling it the gravicembalo con piano e forte, later shortened to pianoforte. His design allowed players to control dynamics by adjusting the force with which each key was struck.
Keyboard instruments are grouped by how they produce sound: aerophones (pipe organ, pump organ, accordion), idiophones (celesta, carillon), chordophones (harpsichord, clavichord, piano, hurdy-gurdy), and electrophones (synthesizers, electric pianos, mellotron, electronic organs). The classification is based on the method of sound production, not on the shared keyboard interface.
In historical musicology, keyboard refers to an instrument whose precise identity cannot be firmly established from the evidence. Particularly in the eighteenth century, the harpsichord, clavichord, and early piano were all in use and the same piece could be played on any of them, so the word keyboard is used as an all-inclusive term.
The current piano is distinct in both sound and appearance from the instruments known to Mozart, Haydn, and Beethoven. It is the product of developments made since the late nineteenth century, building on Cristofori's 1698 design through successive refinements in range, power, and mechanical precision.
A carillon is an idiophone keyboard instrument whose keys are usually housed in bell towers or belfries of churches or municipal buildings, physically separating the player from the sounding bells. Unlike most keyboard instruments, its sound comes from the vibration of struck solid materials rather than strings, air, or electronics.