Scientific denomination.
The term Hinduism has a persian, not indian, origin. It comes from the persian word Hindus, which indicates the Indus river. So, etymologically speaking, it has not a strictly religious significance, but refers to the population settled in the valley of a certain river. It has been used in a religious meaning from the XVII sec. CE by turkish conquerers of islamic faith to identify all those people who hadn't faith in the revealed scripture. That is, people who weren't either jews, christians or muslims.
So the term Hinduism has not been a self-conscious definition the population of the indian subcontinent gave themselves, but something external, which has then been used as a handy historiographic category by Europeans when they started to study the Indian culture.
Nowadays the term Hinduism is generally accepted as a "umbrella" which covers an incredible number of different religious-philosophical trends and movements, with both overlappings and contrasts between them. Other religious traditions of Indian origin, such as Buddhism, Sikhism and Jainism, are usually taken out of the picture because they are characterized by a historical or quasi-historical founder, while there is no such acknowledged founder in the traditions that comes under the the "Hinduism " umbrella
How, then, do Indians name their traditional religion? A largely accepted term is Sanatana Dharma, which means " eternal law", "everlasting norm". "Law" (Dharma) has not here the meaning of a mere code of conduct, but tends more to be conceived as the transcendental cosmic principle which sustain all reality.

Place of origin.
According to many experts, the origins of Hinduism date back to roughly 1750- 1300 BCE., when Indo-Aryan tribes coming from central Asia settled in the north of India, expelled the former Indo-valley inhabitants and developed some philosophical concepts and social practices that constitute the basis of the Hindus philosophical and religious system.

 

Current distribution among world population.
Hindus are the third largest religious community in the world (after Christians and Muslims) and number almost one billion, living in 84 countries. Most of them live in southern Asia, particularly in India, Nepal, Sri Lanka, Bhutan, Malaysia, Singapore, and Indonesia (Bali). There are Hindus communities in Africa (Mauritius), in Latin America (Guyana, Trinidad), in the Fiji islands, the United States, and various European countries.

Main doctrinal tenets: overview
Even if Hinduism should be understood as a set of different religious movements, there are nonetheless some shared beliefs. The core of the Hindus faith is the belief in an Absolute, called Brahman, which is etymologically linked to the root brh (to expand, to grow). It is the eternal ground of reality, which is behind a world in cyclical flux of birth, development and destruction. Because of this impermanent character of its phenomena, the world is understood as Maya. Maya is the extraordinary power of Brahman. The word Maya means unreal, illusory, or deceptive image of the creation. Due to the power of Maya one considers the universe as existent and distinct from Brahman. Maya and Brahman are inseparable like fire and heat. Brahman can be conceived either as a impersonal principle or as a Supreme God. Its counterpart is the Atman, the equivalent of the Brahman concealed in every individual, a sparkle of eternity inside every human being. The recognition of this equivalence of the Atman and the Brahman - that is, the recognition of the eternity of the innermost part of the individual - represents the ideal goal for all Hindus religious traditions. This salvation can be reached in various ways, by means of ritual, ascetic practice or devotion.

Contextualization and Analysis of the sources:

Source n° 1
Ohm Mantra
A Mantra is a particular utterance in Sanskrit language, largely used in the context of Hindu religions and it is typically conceived as having a peculiar power of its own. It is thought to influence reality, the psychological and spiritual dimensions of the practitioner who recite it. They are used as a way to worship deities as well.
The Ohm Mantra in generally accepted as one of the foremost symbols of Hinduism. Originally it means "yes" and it was constantly repeated by the priest during the rituals to confirm the correct execution. It is a diphthong formed by the letter A + U (which become O) + M and it is revered as the acoustic manifestation of the working of the Absolute.
The letter A symbolizes the act of creation of reality which stems from the Absolute, the U its preservation, the M its dissolution and re-absorption within the Brahman. Finally, the gradual fading into silence of the sound of the M is understood as a "fourth sound" which points to the transcendent and inexplicable nature of the Brahman.
In this way the Ohm is a symbol of the main doctrinal tenets discussed above.
This is, of course, just one of the many theological interpretation. The three sounds are symbolically related with other triplets: Earth, Atmosphere, Heaven, three different levels of consciousness (vigil, dreaming, depth-sleeping) and so on. At the ground of each set there is always the Brahman from which everything stems, from the material world to the innermost core of the self (i.e. the Atman).

Source n° 2
Map of religious distribution in India
The map shows that the main religion in India is Hinduism. Hinduism is divided evenly over all the country. Even thought also Buddhism was developed in India, it is not as popular as Hinduism. So Buddhism is shown in this map, and maybe under the other group. There is a small percentage of Christian and  Muslim across the country, too. There is small percentage of Sikh, most of them live in New Delhi area.

 

Intercultural & Interdisciplinary information.
(Philosophy)
Arthur Schopenhauer (1788-1860), in his The World as Will and Representation (1819), employs the kantian concepts of phenomenon and noumenon. The phenomenon is the product of our consciousness , it is the world as it appears , while the noumenon is the thing itself , the foundation and essence of the real world. For Schopenhauer, therefore, the material phenomenon is only semblance , illusion, dream, between us and the true reality. In order to express his idea of something similar to a screen that shows us the distorted reality he use the expression "the veil of Maya" , which he draws from Indian Philosophy. In fact, he was exposed to classical Indian thought in late 1813 by the orientalist Friedrich Majer (1771–1818).