Sudoku - Fun With Numbers

Sudoku is a logic-based integer placement puzzle, made popular by Nikoli Co. Ltd.

, eminent puzzle publishers in Japan.
The goal for the player in this game is to fill up a 9×9 grid so that each column, each row, and each of the nine 3×3 boxes (also called blocks or regions) contains the digits from 1 to 9 only one time each.
A partially populated grid is supplied to the player at the start.
Completed Sudoku puzzles are generally a type of Latin square with an added constraint on the position of numbers in individual regions.

Howard Garns, an American architect, invented the modern Sudoku in 1979.

Dell Magazines published it with the title 'Number Place'.
It gained tremendous popularity in Japan in 1986, when it was published by Nikoli and was monikered 'Sudoku', which means 'single number'.
It turned into an obsession worldwide by 2005. Unlike any other number games, Sudoku does not need to have numbers only.

A game can be created using unique pictures, alphabets, colors or even symbols.
Many different strategies exist which can be used to solve a Sudoku.

Some of the more effective strategies are Marking up, Scanning, Dot and Subscript notations. Scanning is the first phase for cracking the code of a Sudoku puzzle. In scanning, the player observes the location of the numbers already placed in the puzzle grid and notes the relative positions of the numbers. Cross-Hatching, a method of scanning, can be particularly helpful.
In this process, the player marks the rows and columns in which a given number occurs, thereby finding out the perfect spot for that number in a particular 3 x 3 zone. This method is very helpful in solving complex Sudoku puzzles and making simpler puzzles significantly easy to crack.

In Marking up, the player marks the possible positions of the remaining units on the game sheet itself with a pencil.
This helps in fine-tuning the analysis after the initial scanning phase has been completed.

In Subscript notation, the player writes the possible numbers in small size in the individual cells.
If the puzzle is published in a newspaper, the font size may often be too small for this method to succeed. In those cases, the player may decide to create a larger copy of the puzzle.
In Dot Notation, all 9 numbers are placed in each cell with differently colored dots. As the constraints of a particular cell are discovered, the player starts eliminating the dots one at a time.

This process continues until all dots except one has been eliminated for each cell.

This method is slightly tedious, but can be grasped more easily by people who are not so familiar with the Sudoku puzzles.
There are other technical variants of Sudoku, which involve either more, or less number of squares.

There are 6 x 6, 8 x 8 or even giant sized 25 x 25 Sudoku charts. Sudoku is a very popular game nowadays.
Even annual championships are held on this game around the world.

The first championship, which was held in Lucca, Italy in 2006, had numerous industries from countries around the world. That proved the way people had embraced this new magic game of numbers. Sudoku is here to stay, and its popularity can only go up from here.