Keyboard instruments typically produce sound indirectly, all of polyphonic and harmonic with a range of heights that far exceeds that of other instruments of the orchestra.
The organ (Pipe Organ) is one of the oldest instruments keyboard. In Rome we find hydraulic components which use water to produce the notes, but it is in the Renaissance when it becomes an important instrument.
Piano, celesta key and have a keyboard and a similar way, but the material and shape of what changes excite sound. Keyboards continue to evolve and be considered a computer and keyboard instrument.
Electric instruments began without recognizable interpretation systems like Martenot waves, but soon saw that keyboards were the best way to access sounds. There arose organs and electric pianos.
In the 50s electronic music took its first steps and in the 60s we find the first synthesizers (1967).
Computers have an alphanumeric keyboard to type and schedule. Again a method of instructing indirectly serves to create music. Touchscreens and new sensitivities have created pressure keyboards that Iran joining existing instruments with greater or lesser success.
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