Different types of quadrilaterals are explained with their definition and properties along with the diagram.

Parallelogram

A quadrilateral is called a parallelogram, if both pairs of its opposite sides are parallel.

AB ∥ DC and AD ∥ BC.

So, ABCD is a parallelogram.

Rhombus

A parallelogram having all sides equal, is called a rhombus.

In the adjoining figure, ABCD is a rhombus in which

AB ∥ DC, AD ∥ BC and AB = BC = CD = DA.

Rectangle

A parallelogram in which each angle is a right angle is called a rectangle.

AB ∥ DC, AD ∥ BC and ∠A = ∠B = ∠C = ∠D = 90°.

So, ABCD is a rectangle.

Square

A parallelogram in which all the sides are equal and each angle measures 90° is called a square.

AB ∥ DC, AD ∥ BC, AB = BC = CD = DA

and ∠A = ∠B = ∠ C = ∠D = 90°.

So, ABCD is a square.

Trapezium

A quadrilateral having exactly one pair of parallel sides is called a trapezium.

AB ∥ DC.

So, ABCD is a trapezium.

Isosceles Trapezium

A trapezium whose non-parallel sides are equal is called an isosceles trapezium.

Thus, in the adjoining figure, ABCD will be an isosceles trapezium if

AD ∥ BC and AB = BC

Kite

A quadrilateral is called a kite if it has two pairs of equal adjacent sides but unequal opposite sides.

AB = AD, BC = DC, AD ≠ BC and AB ≠ DC.

So, ABCD is a kite.