Learning Sudoku

I am such a numbers boffin and here Carol is trying to teach me the game of sudoku (did I spell it right?) Anyway, like algebra never made any sense, this doesn't, well it kinda does but I don't think I will get as addicted to it as Carol is. It is a good exercise to keep the brain tuned, so I will stick at it.....
Deep in concentration and no idea really.......