The dark

What do we know of black?  Of the dark?  Little.  When you turn your lights out.  If the room is pitch black.  You may think nothing is there.  But you don't know.  You can't see.  Dark, true dark, the kind that seems like a wall in front of your face.  What do you know of that?  Even less.  What makes some dark feel different than others?  What makes some dark feel comforting and other dark frightening?  I love the dark.  And all of its unknowns.