Better Ask ..... Old D-Table

I thought I better ask about this. I think these are called D-Tables (?) and not sure IF this is old or not -- but I just thought I would mention that it is put together with *NO Nails* at all. It fits together with notches etc. Would this be considered Arts and Crafts furniture IF no nails used?

~ Would this help date the item?
~ What type of wood might it be?

Thanks for any help.....I always just wondered about this little table. I love it!!

;-)