Su Doku is a japanese name short for "Suji wa dokushin ni kagiru" which means "the numbers must occur only once".
Sudoku puzzles became popular in Japan following their inclusion in Monthly Nikolist in April 1984 but in
actual fact the first Sudoku puzzles were published in Dell Pencil Puzzles and Word Games in New York in 1979
going by the name of Number Place.
Today Sudoku puzzles can be found in many, many daily publications in Britain, Holland, Japan, the USA and many other
countries.
What is Sudoku?
Sudoku is a puzzle where the puzzler has to fill in the empty squares in a grid. Skill in mathematics is not needed,
only logic and strategy are required.
The grid itself consists of 9 rows and 9 columns which are subdivided into 9 blocks each with 3 rows and 3 columns
as shown here.
Fig 1. Empty sudoku grid
When solved correctly each row, column and 3 by 3 block of numbers must contain the digits 1 to 9 once only.
A Sudoku grid typically contains around 25 to 30 numbers to start with.
The remaining blank squares have to be solved using strategies of deductive reasoning. One such technique is
scanning where the puzzler must scan the rows, columns and blocks to solve squares by a process of elimination.
It is discovering and mastering new solving techniques that takes the Sudoku puzzler onto new levels of
ability and addiction!
Where does Sudoku come from?
