What makes sudoku puzzles so easy?

Sudoku puzzles are actually not inherently easy. They are often perceived as easy because:

* Beginner levels are very simple. Many people start with very basic Sudoku puzzles that have a high number of givens (pre-filled numbers). These puzzles are designed to be introductory and can be solved with basic logic.

* The rules are simple. The core rules are easy to understand and apply. You just need to fill in the grid with numbers 1-9, making sure each number appears only once in each row, column, and 3x3 block.

* There are no complex calculations. Sudoku is a logic puzzle, not a math puzzle. You don't need to do any calculations or advanced mathematical operations.

* Visual aids and strategies exist. There are many visual aids and strategies like pencil marking techniques (candidates) and elimination strategies that make solving easier, especially for beginners.

However, Sudoku puzzles can be very challenging:

* Difficulty levels vary. The difficulty of a Sudoku puzzle depends on the number of givens and the complexity of the logic required to solve it. There are extremely difficult Sudoku puzzles with very few givens that require advanced strategies and a high level of logical thinking.

* Advanced puzzles require complex logic. More difficult Sudoku puzzles can involve sophisticated deduction techniques and multiple layers of logic.

* Time pressure adds difficulty. Even simple Sudoku puzzles can become challenging when solved under time pressure.

Overall, the perceived ease of Sudoku puzzles comes from the simple rules and the availability of beginner-friendly puzzles. But, just like any puzzle, the difficulty can vary significantly, and some Sudoku puzzles can be incredibly challenging.