Hindus believe in the Supersoul from which other souls are born in the form of lives.
After the completion of the life-cycle of human beings or return to the Supersoul, they merge with it, depending upon the deeds and merits they have accumulated in their life-time.
Lord Shiva is the Supersoul and prevails over everything and is everywhere.
In other words, he is the source of all divine powers, all living and non-living beings.
The universe is created by Shiva in his own image for he is Unlimited Consciousness and consciousness alone exists.
In the concept of Swatantriya (absolute independence) in the Shaiva philosophy, it is the soveriegnty of will which makes him both imminent and transcendent while form and space do not limit him.
He has endowed each individual with three inherent faculties of will, cognition and action.
These faculties, when in perfect harmony, lead the individual to a state of Eternal Bliss.
Shiva is called Om which represents the five elements of the process of a life-cycle. Om has three sound elements
which give the sounds of vowels, such as 'A', 'Ou' and 'Ma', and two physical elements, such as a 'dot' and a
'A' represents birth, 'Ou' is life, 'Ma' is death, 'dot' is disintegration of the body into original five elements (Wind, Water, Fire, Earth, and Space aka Ether)
and 'crescent' is the soul moving to another physical body or returning to merge with the Supersoul.
In the human form, each element of this life-cycle process also represents one face each of the five faces of Shiva. Therefore, Om
also stands for Shiva and denotes the Universe.
Shiva is depicted as a five-faced form to represent these five elements that support life on earth. Each face has
three eyes, which also represent birth, life and death.
Shiva appears as a luminous lingam. Although it has a special form, the Lingam is considered as a formless and
infinite object representing him as the universe. The base of the object representing 'Ou' is considered to be
'Om' which depicts him and the Universe. Such a set is worshipped as Shiva everywhere in the Hindu
world. The lingam also is supposed to have five faces. Four faces are usually carved on all four directions and the
fifth, which is not carved, is facing upwards.
Shiva represents the life-cycle and five life-supporting elements which have a form of five faces representing the
five elements. The life-cycle represents the creation of life from five elements such as earth, water, fire, air and
ether, then the maintenance of life and the completion of life, i.e. death, which means separating the physical body
from the soul. The body disintegrates into five elements and returns to their original elementary forms.
A lot of the time in Hindu religion, people pray to a god for a specific reason.
Typical ones are like Ganesh, for good luck.
Shiva is worshipped for his supreme power and Durga is worshipped by married women for a happy married life or strength to conquer evil within.