Hinduism: Hindu mythology is rich, multifarious, and inclusive. It portrays the terrible alongside the benevolent, the trivial alongside the cosmic, and the grotesque alongside the sublime. Unlike Islam, Sikhism and Christianity, Hinduism does not have one holy book, but the important texts are Rig Veda, Upanishad and Bhagvad Gita. The earliest source of Hindu mythology is the Vedic literature, the oldest texts of which are the four Vedas, or "Books of Knowledge": Rigveda, Yajurveda, Samaveda, and Atharvaveda, and represent the religion of the Aryan invaders of the subcontinent over the period from 1400 to 500 BC.
Hinduism is not an idea but a power, not an intellectual proposition but a life's conviction. Many Hindus also accept that there are four major human goals; material prosperity (artha), the satisfaction of desires (karma), performing duties laid down according to your position in life (dharma), and beyond life, the goal of achieving liberation from endless cycles of rebirths into which everyone is locked (moksha). Hinduism also beliefs in trinity of Gods, Brahama the creator, Vishnu the Preserver and Shiva the destroyer.
Because it integrates a variety of heterogeneous elements, Hinduism constitutes a complex but largely continuous whole; and, because it covers the whole of life, it has religious, social, economic, literary, and artistic aspects. Hinduism thus resists a precise definition, but a common core of characteristics most Hindus share can be identified. There are countless rituals practiced within Hinduism many of which are practiced by people of other religions.
Hinduism is a religion with various Gods and Goddesses. According to Hinduism, three Gods rule the world. Brahma: the creator; Vishnu: the preserver and Shiva: the destroyer. These three Lords have consorts and they are goddesses too. Consort of Brahma is Sarasvati; goddess of learning. Vishnu's consort is Lakshmi; goddess of wealth and prosperity. Shiva's consort is Parvati who is worshipped as Kali or Durga.
Besides these there are a number of other Gods and Goddesses. To name a few, there is Ganesh, who has an elephant's head and he is also a son of Shiva and Parvati; Hanuman, who is an ape; Surya Lord of sun; Ganga Ma, Goddess of river Ganges; Samundra, Lord of the sea; Indra, king of the Gods; Prithvi, Goddess of earth; Shakti, Goddess of strength.
Some gods have more than one name. Shiva is also known as Shankar, Mahadev, Natraj, Mahesh amongst others. His worshippers also worship images of bull called Nandi, who was Shiva's carrier and a unique stone design connected to Shiva called the Shiva-Lingham. Ganesh is also called Ganpati. Lord Vishnu went about preserving the world by incarnating 10 times in human forms in times of crisis, and in his every appearance he had a different form which are also worshipped as Gods. Among his appearances, he appeared as Rama, Krishna, Narsimha, Parsuram and Buddha. Krishna also has different names, Gopal; Kishan; Shyam and other names. There are also Gods who can change their forms, such as Parvati who can change into Kali or Durga.
Not all of these Gods are worshipped by all Hindus, with some Hindus worshipping specific Gods or Goddesses, and some of these have predominance in some regions. Hindus also worship Gods according to their personal needs; those engaged in wrestling, body building and other physical sports worship Hanuman, who in Hindu legends was an ape with lot of physical strength; and those in business worship Lakshmi, Goddess of wealth.
Though these Hindus worship different idols, there are many Hindus who believe in one God and perceive in these different Gods and Goddesses as different images of the same one God. According to their beliefs, idolatry is the wrong interpretation of Hinduism.
A unique and all-encompassing characteristic of Hinduism is that one devotee may be worshipping Ganesha while a friend worships Siva or Vishnu or Kali, yet both honor the other's choice and feel no sense of conflict. The Hindu religion brings us the gift of tolerance that allows for different stages of worship, different and personal expressions of devotion and even different Gods to guide our life on this earth. You will thus find Hindu temples for different Gods and Goddesses in near proximity to each other. Indeed, you will find places of worship for many different faiths in close proximity to each other. About 80% of the population are Hindus, thus by far the most common religion in India.
One of the unique aspects of Hinduism are its countless rituals for just about every occasion.