Take EDM for example; it's a combination of words and sounds all cramed together to create a piece of music, most of the time it has no official reason or back story but is simply made to be enjoyed. This concept is the same with Jazz music. When jazz was invented there was no definitive reason or way to play it, you just grabbed an instrument and started playing whatever cords and rhythms you thought sounded nice.
The frets could be somewhere alongside the neck. Some diagrams are in favor of vertically oriented, rather than horizontally. But they function the same way, just turn it 90 degrees clockwise. So, the answer is fretboard diagrams can be oriented vertically or horizontally.
Answer:
usually, the home row keys are : a, s, d, f, g, h, j, k, l, ;
so i´m guessing g and h!
Explanation:
i hope this is right and helps!