Enlarge this image. Fragment of a four-faced linga, 900–1000. Central India. Sandstone. Courtesy of the Asian Art Museum, Gift of Edward Nagel, B71S10.
Hinduism is one of the world’s oldest religions. It has complex roots, and involves a vast array of practices and a host of deities. Its plethora of forms and beliefs reflects the tremendous diversity of India, where most of its one billion followers reside. Hinduism is more than a religion. It is a culture, a way of life, and a code of behavior. This is reflected in a term Indians use to describe the Hindu religion: Sanatana Dharma, which means eternal faith, or the eternal way things are (truth).
The word Hinduism derives from a Persian term denoting the inhabitants of the land beyond the Indus, a river in present-day Pakistan. By the early nineteenth century the term had entered popular English usage to describe the predominant religious traditions of South Asia, and it is now used by Hindus themselves. Hindu beliefs and practices are enormously diverse, varying over time and among individuals, communities, and regional areas.
Unlike Buddhism, Jainism, or Sikhism, Hinduism has no historical founder. Its authority rests instead upon a large body of sacred texts that provide Hindus with rules governing rituals, worship, pilgrimage, and daily activities, among many other things. Although the oldest of these texts may date back four thousand years, the earliest surviving Hindu images and temples were created some two thousand years later.

What are the roots of Hinduism?

Hinduism developed over many centuries from a variety of sources: cultural practices, sacred texts, and philosophical movements, as well as local popular beliefs. The combination of these factors is what accounts for the varied and diverse nature of Hindu practices and beliefs. Hinduism developed from several sources:
Prehistoric and Neolithic culture, which left material evidence including abundant rock and cave paintings of bulls and cows, indicating an early interest in the sacred nature of these animals.
The Indus Valley civilization, located in what is now Pakistan and northwestern India, which flourished between approximately 2500 and 1700 B.C.E., and persisted with some regional presence as late as 800 B.C.E. The civilization reached its high point in the cities of Harrapa and Mohenjo-Daro. Although the physical remains of these large urban complexes have not produced a great deal of explicit religious imagery, archaeologists have recovered some intriguing items, including an abundance of seals depicting bulls, among these a few exceptional examples illustrating figures seated in yogic positions; terracotta female figures that suggest fertility; and small anthropomorphic sculptures made of stone and bronze. Material evidence found at these sites also includes prototypes of stone linga (phallic emblems of the Hindu god Shiva). Later textual sources assert that indigenous peoples of this area engaged in linga worship.
According to recent theories, Indus Valley peoples migrated to the Gangetic region of India and blended with indigenous cultures, after the decline of civilization in the Indus Valley. A separate group of Indo-European speaking people migrated to the subcontinent from West Asia. These peoples brought with them ritual life including fire sacrifices presided over by priests, and a set of hymns and poems collectively known as the Vedas.
The indigenous beliefs of the pre-Vedic peoples of the subcontinent of India encompassed a variety of local practices based on agrarian fertility cults and local nature spirits. Vedic writings refer to the worship of images, tutelary divinities, and the phallus.