One of the most often asked questions I hear on boards concerning members' guitars, especially the acoustics, is "what wood is it made of?"
We can't be 100% certain of course but we take an educated guess based on experience, and most of the time I think we get it right.
At the shop where I work, we're a Taylor dealer, and while browsing their web site I came across this nice little wood comparison. I thought it might be helpful to those wanting a quick schooling in many of the more popular and some of the more exotic woods out there:
http://www.taylorguitars.com/guitars/acoustic/woods