Hinduism (/ˈhɪnduɪzəm/) is an Indian religion or dharma, a religious and universal order or way of life by which followers abide. As a religion, it is the world's third-largest, with over 1.2–1.35 billion followers, or 15–16% of the global population, known as Hindus.
Hinduism is one of the oldest religions in the world and has its roots in the Indus Valley Civilization, which existed between 2600 BCE and 1900 BCE. The early forms of Hinduism were polytheistic and included worship of the gods Indra, Agni, Varuna, and Surya.
The Vedas, a collection of ancient Hindu scriptures, were written between 1500 BCE and 500 BCE and contain hymns, prayers, and rituals that were used in Vedic ceremonies. The Upanishads, another set of Hindu scriptures, were written around 800 BCE and contain philosophical and metaphysical discussions about the nature of reality and the soul.
In the 6th century BCE, Hinduism underwent significant changes with the emergence of new religious and philosophical ideas. The teachings of Buddha and Mahavira, the founders of Buddhism and Jainism respectively, influenced Hinduism greatly during this period.
The Bhagavad Gita, a sacred Hindu scripture, was written around 400 BCE and is considered one of the most important texts in Hinduism. It contains a conversation between the god Krishna and the warrior Arjuna, and explores themes of duty, ethics, and spirituality.
During the medieval period, Hinduism underwent significant changes with the rise of the Bhakti movement, which emphasized devotion to a personal god. The movement was characterized by the worship of deities such as Vishnu, Shiva, and the goddess Devi.
In the 19th and 20th centuries, Hinduism experienced a revival with the emergence of various reform movements that sought to modernize and reinvigorate the religion. The Arya Samaj and the Ramakrishna Mission were among the most prominent of these movements.
Today, Hinduism is the third-largest religion in the world, with over a billion followers. It is a complex and diverse religion, with many different sects, schools of thought, and practices. Its influence can be seen in many aspects of Indian culture, including art, literature, music, and philosophy.