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