For example in the the above figure, when only E-field component of the electromagnetic wave is traced out on screen perpendicular to the direction of propagation of the electromagnetic wave, we get a straight line. Hence the polarization of this kind of electromagnetic wave is called linear. <br \>

Based on polarization there are three major types of waves:

* '''Linearly polarized:''' The above wave is a example of linearly polarised wave. In linear polarization, the line traced by E-field can be in any orientation.

* '''Circularly polarized:''' Consider two linearly polarised waves of equal magnitude perpendicular to each other. If we create a phase difference of 90° between them and add them, we will get a circular polarized wave. i.e. the E-field of the wave will trace out a circle. The circle can right handed (Right Hand Circular Polarization or RHCP) or left handed (Left Hand Circular Polarization or LHCP) depending on which wave is leading or lagging.

*'''Elliptically polarized:''' If the two linearly polarized waves used for circular polarization have unequal magnitude or are added with phase difference not 90° or 0° or integral multiple of 90°, then the resulting polarization will be elliptical. The ellipse, again, can be right handed or left handed.

[[File:Polarization2.png|center|frame]]

Now, the polarization of any antenna is simple the polarization of electromagnetic waves radiated by that antenna. The reason why polarisation of antenna is so important is it is useful in determining the losses while making the link budget.