Sudoku
Sudoku has undoubtedly been the worldwide puzzle sensation of the last few years. Despite the name, Sudoku (or Su Doku) is not a Japanese puzzle. It owes its origins to the ancient magic squares although without the requirement for adding the numbers.The modern puzzle was invented in America in the 1970s. It was picked up by the Japanese publisher Nikoli some ten years later. In 2004 the Times of London began publishing Sudoku puzzles in the UK and it immediately became extremely popular here. Having conquered the UK, the puzzle then returned to its place of origin to take the US by storm.
Today Sudoku is everywhere - sometimes it seems that it's difficult to buy a newspaper without a Sudoku puzzle! You can also buy computer programs, hand-held Sudoku games and who knows what other stuff.
How To Play Sudoku
Although it uses the digits 1 through 9, Sudoku is a pure logic puzzle. The numbers could be replaced by letters, symbols, or anything else.The rules of Sudoku are extremely simple. A puzzle consists of a 9 by 9 grid of squares subdivided into nine 3 by 3 "subsquares". Each of the 81 small squares must contain one of the digits from 1 to 9. A few squares are given at the start of the puzzle, the others must be deduced by the solver following one simple rule: each row, each column and each 3x3 subsquare must contain exactly one of each digit from 1 to 9.
That's it. So simple yet so addictive.
Sudoku problems are often graded in difficulty. In the easiest problems it is possible to deduce each square without any doubt. In more difficult problems the solver will be required to apply "what if?" logic to determine which solution is correct.
Since the invention of the basic puzzles, people have also designed a number of variations.
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