The most likely candidate for most common fretboard wood is Rosewood. Rosewood is a medium-high density wood. Rosewood is used for fretboards also because of the relative uniformity in coloring and figuring and the lower cost versus ebony.
There are a number of species of Rosewood used in guitar construction and certain species are prized for their figuring. Those are the ones used extensively in the construction of the back and sides of acoustic guitars.
Maple is most commonly seen used in fretboards for bolt-on neck guitars. It takes wear pretty well due to its strength and density but it inevitably discolors badly over time with play.
Ebony is the most highly prized wood for guitar fretboards. It is the darkest in color and densest of the group with the tightest grain pattern. It is also the most expensive and difficult with which to work, which is why so many companies more commonly use Rosewood and/or Maple, even though Ebony is the mre desired wood.