What does the key in the right-hand corner (ignoring the calculator bit) of my keyboard do ? It's between the Windows symbol and Ctrl and is a square with three hyphens in it. I daren't press it to find out in case it's for blowing up the keyboard!
I've often wondered that. Never used it. On my Dell keyboard it is next to the Altgr key to the right of the spacebar. The Altgr key performs the same function as holding down both Ctrl and Alt. Thus if you wish to type the dreaded € symbol (wash my mouth out) you have two ways of doing it.