# Square A **square** is a [[quadrilateral]] with all interior angles $90^\circ$ and all sides the same length. As such, it is a [[regular polygon]]. ## Useful Properties * The diagonals of the square are the same length as each other and meet at right angles. The diagonals are $\sqrt{2}$ times longer than the side length. * The [[symmetry group|symmetries]] of the square are: * four [[rotational symmetry|rotations]], * four [[reflective symmetry|reflections]]. ## Area of a Square The [[area]] of a square is the square of the length of one of its sides. [[!redirects area of a square]] [[!redirects lengths in squares]] [[!redirects lengths in a square]] [[!redirects angles in a square]] [[!redirects angles in squares]] [[!redirects squares]] [[!redirects properties of squares]] [[!redirects properties of a square]]