Futoshiki is a number puzzle game that involves filling a grid with numbers such that each row and column contains the digits 1 to 5 (or 1 to whatever size the grid is) without repetition, and also ensuring that the inequalities between adjacent cells are satisfied.

Here's how to play Futoshiki:

Familiarize yourself with the grid: The grid is a square made up of smaller squares. Each row and column should contain the numbers from 1 to the size of the grid without repetition.

Understand the inequalities: In Futoshiki, some squares have inequalities (e.g. "greater than" or "less than") that indicate the relative size of the numbers in the adjacent squares.

Start filling in the numbers: Using logic and deduction, fill in the numbers starting with the cells that have the least number of possibilities.

Use process of elimination: Keep track of which numbers have already been used in each row and column. This will help you eliminate possibilities for the next number.

Check for errors: Regularly check your work to make sure you haven't made any mistakes.

Solve the puzzle: Keep filling in the numbers and ensuring that the inequalities are satisfied until the entire grid is complete.

Remember, in Futoshiki, each number can only be used once in each row and column, and the inequalities must be satisfied.