India has the world's second-largest population exceeded only by that of China. India crossed the billion mark in May 2000 and is tipped to be the planet's most populous nation in the next couple of decades. Mumbai is India's most populated city, with an urban population of 16 million; Kolkata ranks second with 14 million and Delhi and Chennai third and fourth with - 13.8 and 5.9 million respectively. However, the people of India are not homogenous; various groups look different and there is a plethora of customs, religions and languages.

There is no one 'Indian' language as such. This is part of the reason why English is still widely spoken 50 years after the British left India and why it's still the official language of the judiciary. Eighteen languages are recognized by the constitution, and these fall into two major groups: Indie, or Indo-Aryan, and Dravidian. Additionally, over 1600 minor languages and dialects were listed in the latest census. The scope for misunderstanding can be easily appreciated!

The Indie languages are a branch of the Indo-European group of languages (to which English belongs). The Indie languages were spoken by the Central Asian peoples who invaded what is now India. The Dravidian languages are native to south India, although they have been influenced by Sanskrit and Hindi over the years.

Most of India's languages have their own script, but written English can also be quite common; in some states, such as Gujarat, you'll hardly see a word of it, whereas in Himachal Pradesh virtually everything is in English. For a sample of the different scripts, look at a Rs 5 or larger banknote where 14 languages are represented. As well as Hindi and English there's a list of 12 other languages: from the top, they are Assamese, Bengali, Gujarati, Kannada, Kashmiri, Malayalam, Marathi, Oriya, Punjabi, Sanskrit, Tamil, Telugu and Urdu.

From a postal worker performing puja (prayers) for the safe passage of a parcel, to a former car salesman who has renounced his material life and set off on the path to self-realization, religion suffuses every aspect of life in India.

India's major religion, Hinduism, is practiced by approximately 82% of the population and has the largest number of adherents of any religion in Asia. It is also (along with Buddhism, Jainism and Zoroastrianism) one of the oldest extant religions and has firm roots extending back beyond 1000 BC. The Indus Valley civilization seems to have developed a religion closely related to Hinduism, but it was the Veda scriptures that gave Hinduism its framework.

Buddhism and Jainism arose contemporaneously in the 6th century BC at a time of social and religious ferment. Both were reactions against the strictures of Brahminical Hinduism. Although more recent, Sikhism too has its roots in a protest movement, the bhakti (devotional) tradition of southern India. Islam swept into India from the north and was introduced to the south by Arab traders. Today it's the largest minority religion in the land. Christianity arrived in southern India with Syrian immigrants long before the first European ever dropped anchor in that part of the world. India is also home to one of the world's oldest Jewish communities.

Hinduism defies attempts to define it. It has no founder, central authority nor hierarchy. It is not a proselytizing religion. The multitude of gods and goddesses are merely manifestations - knowable aspects of this formless phenomenon - and one devotee may freely pick and choose among them.

Although beliefs and practices vary widely from region to region, there are several unifying factors. These include samsara (common beliefs in reincarnation), karma (conduct or action) and dharma (appropriate behavior for one's station in life), as well as the caste system.

Hindus believe that earthly life is cyclical; you are born again and again (a process known as samsara), the quality of these rebirths being dependent upon your karma in previous lives. Living a righteous life and fulfilling your dharma will enhance your chances of being born into a higher caste and better circumstances. Alternatively, if enough bad karma has accumulated, rebirth may take animal form. But it's only as a human that you can gain sufficient self-knowledge to escape the cycle of reincarnation and achieve moksha (liberation). Traditionally, women are unable to attain moksha. The best they can do is fulfill their dharma and hope for a male incarnation next time round.

Essentially there are three stages in life recognized under this ashrama system: brahmachari (chaste student); grihastha (householder who discharges their duty to their ancestors by having sons and making sacrifices to the gods); and sanyasin (wandering ascetic who has renounced worldly things; The disinterested discharge of your ritual and social obligations is known as karma-mar and is one path to liberation. But there are others, including jnana-marga, or the way of knowledge (the study and practice of yogi and meditation) and bhakti-marga, devotion to a personal god.