The piano, invented around 1700 by Bartolomeo Cristofori, revolutionized keyboard instruments by allowing for dynamic control, enabling players to play both soft and loud tones, a feature absent in the harpsichord. 

Here's a more detailed look:

Inventor:

Bartolomeo Cristofori (1655-1731), an Italian instrument maker, is credited with inventing the piano. 

Invention Date:

Around 1700. 

Motivation:

Cristofori was dissatisfied with the harpsichord's lack of dynamic control, where the volume was fixed. 

Key Innovation:

He replaced the harpsichord's plucking mechanism with a hammer action, allowing for a wider range of volume control, hence the name "pianoforte" (meaning "soft-loud" in Italian). 

Early Pianos:

Cristofori's early pianos, known as "clavicembalo col piano e forte," featured hammers and dampers, two keyboards, and a range of four octaves. 

Evolution:

Over time, the piano evolved, with improvements in mechanism, sound production, and design, leading to the modern piano we know today. 

Cristofori's Role:

Cristofori was employed by the Medici family in Florence, and his work laid the foundation for the modern piano. 

Popularity:

While the piano was initially used by wealthy patrons, it gained widespread popularity as it became more affordable and replaced the harpsichord as the preferred keyboard instrument.