No offense asking. It's an Irish Bouzouki. If you're into string music , like a an octave mandolin (an octave lower) but tuned GDad instead of GDae. The two D's produce a droning sound typical of Celtic music (think of pipes). Ciao
Called a bouzouki only because it has a similar scale length to the Mediterranean instrument by that name, but is otherwise more like a mandolin tuned one octave lower and as the other commenter mentioned, often with the E strings dropped to D.
