Most people unfamiliar with Sudoku probably see it as just a partially filled nine-by-nine-unit grid.
But in just a matter of months, the logic puzzle has garnered a massive following, joining crossword puzzles and word jumbles on the pages of daily newspapers around the world.
Although the number game was first developed in 1979 by architect and puzzle constructor Howard Garns, it only began to gain popularity in Japan during the mid-1980s. Sudoku, an abbreviation for the Japanese phrase meaning "the digits must remain single," requires solvers to fill in empty squares by logical deduction.
The nine rows and columns that make up the grid must contain the digits 1 through 9 exactly once. The larger grid is also divided into nine three-by-three boxes, in which the digits 1 through 9 can also only appear once. Although the game uses numbers, most enthusiasts are quick to note it is not a mathematical puzzle.
"Sudoku is based on a sort of deductive reasoning, which sets up possible assumptions that exhaust all the possibilities and checks the logically following results from those assumptions," said philosophy graduate student Woojin Han, who is currently teaching an introductory logic class. "That seems to be why people say that Sudoku just needs simple logic skills."
The Times in Britain started publishing the puzzle in November 2004, and various British newspapers quickly followed suit in the following months.
The game began to catch on in the United States last summer when it appeared in daily newspapers, including the New York Post and USA Today. Books featuring the puzzle were published and climbed bestseller lists.
"[Sudoku puzzles] don't make you feel like you're studying for the SAT verbal section," sophomore Andrea Crane said, pointing to crossword puzzles' dependence on vocabulary. "I've always been better with numbers than with words. I've never been good with crosswords, but they're similar."
Some residents in Few Quadrangle even returned to their rooms this semester to find a Sudoku puzzle taped to their doors.
"One of my [resident advisors] decided he wanted to put the games on the doors," Few Quad Resident Coordinator Allison Burzio said. "I thought it would be a good idea to do something different."
The logic game comes in various levels, but the difficulty of the puzzle has little to do with how many numbers are given. Rather, it has to do with the placement of those given numbers.
Solving the puzzle, which has even spawned a television game show featuring celebrities in Britain, includes scanning and analyzing the given numbers to deduce possible solutions.
But many people have their own specific methods when approaching a new puzzle.
"Usually, there's one [three-by-three] box that's easier to fill in than the others," Crane said of her method to begin filling in grid box by box.
After exhausting her options, Crane said she begins to tackle the puzzle by columns and rows.
Although for some people Sudoku has dethroned the crossword as the puzzle of choice these days, the longevity of the game will only be determined with time.
"I think there's a larger audience [for Sudoku]," Crane said. "Crosswords are a little limited to those people that not only have the vocabulary but also the interest in words-whereas anyone can use the numbers one through nine."
The concept and skills needed to solve Sudoku puzzles may be painfully easy, but their challenging aspect seems to keep puzzlers interested.
"I think that if a person has this kind of reasoning skill and has some [or great] patience, all puzzles can be solved in principle," Han said. "But the key is the caution or patience, rather than logic skills: The skill is so simple."
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