What is polarization?

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Could you explain to me the phenomena of polarization of light? I still don't have a clear view of it.

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Polarization, also called wave polarization, is an expression of the orientation of the lines of electric flux in an electromagnetic field (EM field). Polarization can be constant -- that is, existing in a particular orientation at all times, or it can rotate with each wave cycle.

Polarization is important in wireless communications systems. The physical orientation of a wireless antenna corresponds to the polarization of the radio waves received or transmitted by that antenna. Thus, a vertical antenna receives and emits vertically polarized waves, and a horizontal antenna receives or emits horizontally polarized waves. The best short-range communications is obtained when the transmitting and receiving (source and destination) antennas have the same polarization. The least efficient short-range communications usually take place when the two antennas are at right angles (for example, one horizontal and one vertical). Over long distances, the atmosphere can cause the polarization of a radio wave to fluctuate, so the distinction between horizontal and vertical becomes less significant.

Some wireless antennas transmit and receive EM waves whose polarization rotates 360 degrees with each complete wave cycle. This type of polarization called elliptical or circular polarization can be either clockwise or counterclockwise. The best communications results are obtained when the transmitting and receiving antennas have the same sense of polarization (both clockwise or both counterclockwise). The worst communications usually take place when the two antennas radiate and receive in the opposite sense (one clockwise and the other counterclockwise).

Polarization affects the propagation of EM fields at infrared (IR), visible, ultraviolet (UV), and even X-ray wavelengths. In ordinary visible light, there are numerous wave components at random polarization angles. When such light is passed through a special filter, the filter blocks all light except that having a certain polarization. When two polarizing filters are placed so a ray of light passes through them both, the amount of light transmitted depends on the angle of the polarizing filters with respect to each other. The lightest is transmitted when the two filters are oriented so they polarize light in the same direction. The least light is transmitted when the filters are oriented at right angles to each other.

The effect of polarization on visible light can be striking. Anyone who has worn polarized sunglasses, or who has used polarizing filters in photography, knows how a clear sky polarizes sunlight. Polarized sunglasses can reduce glare reflected from surfaces; this is useful under certain driving conditions and can also make it easier to see beneath the surface of a body of water. In twisted nematic displays (TN displays), polarizing filters are used in conjunction with a special liquid to brighten and darken regions of the display as external voltages are applied. This makes it possible to display alphanumeric characters in wristwatches, cell phones, and various other consumer electronic devices.

https://whatis.techtarget.com/definition/polarization-wave-polarization
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Polarisation is a property of transverse waves which describes the orientation of the oscillations in the plane perpendicular to the wave's direction of travel. This concept is used in the areas of science & technology dealing with wave propagation such as optics, seismology, and telecommunications.
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Polarization (Brit. polarisation) is a property of transverse waves which describes the orientation of the oscillations in the plane perpendicular to the wave's direction of travel. This concept is used in areas of science and technology dealing with wave propagation, such as optics, seismology, and telecommunications. In electrodynamics, polarization characterizes electromagnetic waves, such as light, by specifying the direction of the wave's electric field. Longitudinal waves such as sound waves in liquids and gases do not exhibit polarization, because for these waves the direction of oscillation is along (and thus is uniquely determined by) the direction of wave's travel. In contrast, the direction of the (electric field) oscillation in electromagnetic waves is not uniquely determined by the direction of propagation. Similarly, the direction of shear stress in a transverse sound wave in a solid can have any orientation in the plane that is perpendicular to the propagation direction. The term polarization thus describes the possible orientations of the oscillatory process in the plane perpendicular to the transverse wave's path.

http://en.wikipedia.org/wiki/Polarization
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Light is an electromagnetic wave it consists of electric and magnetic field vectors vibrating perpendicular to each other and perpendicular to the direction of propagation.

generally, these fields vibrate in all the planes if this is the case the light is said to be UNPOLARISED.

if the vibration of these fields is made to vibrate in only one plane then the light is said to be POLARISED.

we can produce polarised light by means of reflection, refraction, and by means of polarizers.

Generally, we consider only the electric field bcoz the magnetic field is weak
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Light consists of electric and magnetic fields traveling mutually perpendicular to each other. When, somehow, one of these is removed, such that the light has waves only in one dimension, that light is known as polarized light, and the process of making light polarized is known as polarization.
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the phenomenon in which light waves move in one plane.

property of certain electromagnetic radiations in which the direction and magnitude of the vibrating electric field are related in a specified way.
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