The History of Sudoku

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Sudoku Origins

The word Sudoku (sū-dō'kū) is a Japanese contraction, suuji wa - dokushin ni kagiru, meaning (more or less) "uncoupled numbers" or "numbers occurring as singles." Ah, the poverty of the English language.

However, the origin of the Sudoku puzzle itself is not Japanese. No: under the name Number Place, Sudoku puzzles were published in a New York-based puzzle magazine, 1979, where they were soundly ignored by every New Yorker alive in the city at the time.

In 1984, Number Place stormed the Japanese coastline like Godzilla surfing in on a tsunami. The popularity of the game was such that the name "Number Place" was scrapped as a bad job and replaced with the excitingly fresh Japanese equivalent of the name "Numbers Occurring as Singles." Very creative. We're very impressed. Very.

The Sudoku Craze

At long last, planet Earth has caught up with Japanese tailcoats. By the year 2005, even New Yorkers were playing Sudoku. You can usually find a daily Sudoku puzzle in your favorite daily newspaper or magazine, but impatient fans tend to buy dime store Sudoku collections or larger compilations found in nearly every single bookstore in the entire world. Yesterday, the Sudoku Tips and Tricks crew even found a Sudoku section at the Used, Rare and Collectible bookstore down the block. No. Not really. But you can see what we are talking about: Sudoko is rapidly becoming a classic.

Thanks to the internet, there are new and plentiful ways to get your hands on Sudoku puzzles, solutions and, yes indeed, lessons to make you a happy, confident black belt master of Sudoku. Many of those plentiful ways are also free. For example, close your eyes and think fanciful thoughts. When you are done, open your eyes and gaze with delight at Sudoku Tips and Tricks.

We are your doorway to Sudoku satisfaction. Every day, or nearly, we are adding new Sudoku lessons to our website, which are yours to read or print absolutely free. In addition, we are making available Sudoku puzzles for all skill levels between the range of Silly Infant and Advanced Guru. Go ahead, print them out and play them all you want. Yes, for free.

Do you have a website? Are you interested in posting something you see here into your own website? We suggest summarizing a paragraph or two and then politely linking directly to the Sudoku Tips and Tricks article post that's got you so excited. We thank you very much for that small courtesy.

Bag O' Tricks: Sudoku Links

Sudoku Basics: The Rules of the Game

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The Sudoku Grid

Sudoku is a number puzzle played on a board divided into a 9x9 grid, and divided again into nine 3x3 boxes, as in Example 1A:

The Sudoku Mission

Your goal is to complete the 9x9 Sudoku grid so that each of the smaller 3x3 boxes contains every number between one and nine.

Sounds easy, huh? Take another look, Speed Racer. While completing each 3x3 box, you must also make sure that every row and every column of the 9x9 Sudoku grid also contains every number between one and nine. If you happen to be counting, you'll realize that there's only room for nine numbers in a given row or column. Nope: no room for extras or doubles.

An Empty Sudoku Puzzle

Example 1B is a reasonably simple example of what an "empty" Sudoku puzzle will look like before you get started:

Yes. The "empty" Sudoku puzzle isn't empty. Count your lucky chickens: every Sudoku puzzle begins with a gaggle of numbers already in place. In general, the easier the Sudoku puzzle, the more numbers you will find already pinned to the Sudoku grid. As the puzzles become more complicated, you will need to dig out a heavy bag of Sudoku tricks to satisfactorily complete your mission.

Take a look at the top row of Sudoku Example 1B. You begin with six of the nine numbers filled in, leaving you three numbers to identify for yourself: you still need the 4, 6 and 8 to complete the row. The first of these empty squares also sits at the top of a column. After some careful examination, you should see that this column already contains the 4 and 8. Therefore you cannot use either the 4 or 8 to fulfill the needs of your row. This, of course, lets you know how to fill that first empty square. Yes, it IS a 6. Very well done.

The Completed Sudoku Puzzle

Your job, of course, is to add numbers to the empty boxes until your Sudoku grid is full and fat, beautiful in every way. For example take a look at this (feel free not to look until you've successfully completed the puzzle yourself, as you like. I'm not the boss of you):

Learning to Solve Sudoku Puzzles

Now that you know the basic rules of Sudoku, it's time to learn how to play. First, you will need to know the smartest way to look at the puzzle board. The next step involves learning simple strategies for locating those empty boxes that are on their knees begging you for a matching number. Once you master these beginner tips, you might want to peek into the intermediate tricks of the Sudoku trade.

Ready to beat the game?
Free Sudoku Lessons

As always, Sudoku Tips and Tricks allows you to print out every Sudoku puzzle you find at our site. Every puzzle is clickable: when you click, we'll open the grid for you in a fresh, printable window. Print free and freely share with your friends. If you post one of our examples somewhere on the web, please credit Sudoku Tips and Tricks with a link on your web site.

Bag O' Tricks: Sudoku Links