## What is Sudoku?

**Sudoku is a logic-based**, combinatorial number-placement **puzzle**. The concept of Sudoku puzzle is simple. The objective is to fill a 9x9 grid so that each row, each column, and each of the nine 3x3 boxes (also called blocks or regions) contains the digits from 1 to 9 only one time each.

## How to Play Sudoku?

**Sudoku puzzle requires no special calculation or arithmetic skills.** It is essentially a game of placing numbers in boxes, using very simple rules of logic and deduction. It can be played by children and adults and the rules are simple to learn. Sudoku is easy to learn but a challenge to master.

There is really only one rule to Sudoku: **Fill in the game board so that the numbers 1 through 9 occur exactly once in each row, column, and 3x3 box**. The numbers can appear in any order and diagonals are not considered. Your initial game board will consist of several numbers that are already placed. Those numbers cannot be changed. Your goal is to fill in the empty boxes following the simple rule above. **Enjoy playing Sudoku online at PlaySudoku.Org!**