Sudoku is a logic puzzle. You are presented with a grid of squares, 9×9, divided into 9 “regions” of 9 squares each.
The numbers 1 through 9 need to appear once in each row, column, and region. A certain number of squares are already filled in (called “givens”) and it is from these clues that you must derive the values for the rest of the grid.
It uses numbers, but purely as a convenience; there is no math involved. It takes simple deductive and inductive reasoning. There is no need to guess.
It was invented in the seventies, became a huge fad in Japan in the nineties, and took off like a shot in the UK and the US in 2005. Most of your major newspapers have a daily Sudoku grid and there are websites all over the place.
Hooked enough that the wife bought me a book of Sudoku grids. It takes me a little less than an hour to do one of the “Fiendish” difficulty puzzles. I usually do one on the commute home.
I’ve got a Sudoku application for my Palm PDA (after having tried several) and even went so far as to buy a game for my cell phone that allows me to download the Sudoku grid from USA Today. I have another book with even more puzzles waiting for me to finish this one. I use Bloglines to read newsfeeds and blogs and one of my subscriptions is to The Daily SuDoku.
Okay, it’s a little over-the-top, but most of those resources are of the “break here in case of emergency” variety. Just in case I don’t have a Sudoku grid to hand I’ll be able to get one easily.
One of the things I like about it is that while I’m working on a grid, my mind is quiet. The thousands of day-to-day distractions are forgotten for a while as I fill little numbers into a grid. It’s actually very calming. It also has the added benefit of stimulating my brain, helping stave off Alzheimer’s for a little while longer.
Won’t you join me?