A square is a polygon with four sides. A polygon is defined as a closed plane figure with three or more sides. The sides of a polygon are line segments.
A square has four angles and two diagonals. The diagonals of a square bisect each other and are equal in length. In a square, all four sides are equal in length, and all four angles are right angles. A polygon is named according to the number of sides it has. A polygon with four sides is called a quadrilateral. Similarly, a polygon with five sides is called a pentagon, and one with six sides is called a hexagon.