The X-Wing is a powerful advanced Sudoku technique that uses a unique pattern of Xs and Os to solve for missing numbers. It's like a lightsaber for your brain.
When you see two cells in the same row or column that contain the same number, and that number is not in the same row or column as another cell with the same number, it's an X-Wing. This is your opportunity to make an educated guess and solve for the missing number.
For example, if you see the following:
| 3 | ||
| 3 |
Look for the X-Wing by examining rows or columns for duplicate numbers. If you see the following:
| 3 | |
Then you can make a safe guess that the missing number is the one in the middle cell.
But don't just stop there! The X-Wing is just the beginning. Use it as a springboard to solve the rest of the puzzle.