There is a lot of debate about the precise number of keys on a piano. The key size varies according to how it is set and played. An upright piano for example is often a four fret piano, with all the strings of every four strings tuned to the same pitch (four octaves above the middle). The keys are all the same length, and this means that they are all of the same height.
The other key for beginners is the fretboard. The key is flat, and it starts at the lowest frets (e.g. E in F. The fretboard is usually in the same position as the keys on a piano, that is, the fret line is flat and the top of the fret line remains flat). In this respect, it is a ‘lower’ key than the others.
There is a similar debate about the ideal number of frets, and when is too many of them too limiting for a piano beginner. The same principle applies to chords; the chord at D is a minor chord, for example. A D major chord is a major chord.
You should set any piano to a suitable key, by choosing the middle position of the keyboard for the strings, which is the smallest fret for the most number of strings. For example, the C-A-G key will set you to a large octave of piano fretboard in C. It is recommended that the keys are set between 8 and 12 frets, so that each individual finger can play comfortably on that scale.
You can also have a set of strings that is so small that you can play just a single note in that key without using any fingers at all!
You could take a piano apart to experiment with different string gauges – for example an instrument like the Schoppelpusch Grand Stradivarius has over 5000 different string gauges, so it is much more difficult to find a finger sized string that suits your fingers. If you do come across a string smaller than a G the most common question is: “why isn’t it in a guitar string?”, and the answer is actually quite interesting..
The G string would simply not be tuned to the lowest pitch on the piano or guitar, so it would not provide enough strength to hold a finger in that key. So we have to make do with shorter strings.
The second reason for not using the G string is that it is more difficult to play the chord in G, with your index finger. There