**Square** is a quadrilateral with equal sides and angles. The angles of a square are right angles.

The square has all the properties of a rhombus and a rectangle. Like all rhombi, the diagonals of a square are perpendicular. In other words, the angle between the diagonals is a right angle.

$$C=4 \times a$$

where,

a— side length of the square.

Area of square **through side**:

$$S=a^{2},$$

where a is the side length of the square.

Area of square **through diagonal**:

$$S=\frac{d^{2}}{2},$$

where d is the diagonal of the square.

$$d=a \sqrt{2}$$