Interesting facts about the keyboard
In the early years of piano construction, keys were commonly made from sugar pine. Nowadays they are usually made of spruce or basswood.
Black keys were traditionally made of ebony, and the white keys were covered with strips of ivory. However, since ivory-yielding species are now endangered and protected by treaty, or are illegal in some countries, makers use plastics almost exclusively. Legal ivory can still be obtained in limited quantities. Yamaha developed a plastic called Ivorite intended to mimic the look and feel of ivory, other manufacturers have done likewise.
Almost every modern pianos has 52 white keys and 36 black keys for a total of 88 keys (seven octaves plus a minor third). Many pianos only have 85 keys (seven octaves).
Some piano manufacturers have extended the range further in one or both directions. For example, the Imperial Bösendorfer has nine extra keys at the bass end, giving a total of 97 keys and an eight octave range. More recently, Australian manufacturer Stuart&Sons created a piano with 108 keys, nine full octaves. The extra keys are added primarily for increased resonance from the associated strings, that is, they vibrate sympathetically with other strings whenever the damper pedal is depressed and thus give a fuller tone. Only a very small number of works composed for piano actually use these notes.