The game in question is likely Sudoku, a Japanese puzzle game that has become popular worldwide. The objective of Sudoku is to fill a 9x9 grid with digits so that each column, row, and 3x3 section contain all of the numbers between 1 and 9. While the basic premise is simple, solving a Sudoku puzzle can be quite challenging.
There are a few different methods that one can use to solve a Sudoku puzzle. One common method is to start with the easy numbers first, which are the numbers that only appear once in a given row, column, or section. Once those numbers are filled in, it becomes easier to identify which other numbers go where.
Another method is to look for what are called naked pairs. This means finding two cells in the same row, column, or section that have the same two possible digits. For example, if you see two cells in the same row with the possibilities 2 and 7, then you know those are the only two options for those cells and no other digit can go there. This can help narrow down possibilities for other cells as well.
Sudoku is a great game for people who enjoy puzzles and brain teasers. It's also a good way to sharpen your logic skills. Give it a try next time you're looking for something new to do!