For a country as big as India and with a population that is just as large (it is the second most populous country in the world), it is no surprise that the spoken languages are just as varied and as large. For one who wants to learn any Indian language, the undertaking is going to be daunting because of the added task of learning the particular script form of that language.
National and state languages
Trying to learn all of them will certainly take more than a lifetime or two. Consider this: to date, the country has 15 national languages recognized by the constitution. Within this mix, there are over 1,600 dialects on record, so far.
Added to the above statistics are 18 languages recognized by the Indian constitution as state languages. These state languages are used in schools and in official transactions within their respective states. These are Assamese, Bengali, Gujarati, Hindi, Kannada (Kanarese), Kashmiri, Konkani, Malayalam, Meithei (Manipuri), Marathi, Nepali, Oriya, Punjabi, Sanskrit, Sindhi, Tamil, Telugu, and Urdu.
Citizens of former Indian states (and now independent countries) Pakistan and Bangladesh speak Urdu and Bengali, respectively.
Official and working languages
Today, Hindi is recognized as Indias official language. It is spoken by about 20% of the population, especially in Bihar, Madhya Pradesh, Rajasthan and Uttar Pradesh. However, considering the number of languages spoken all over the country, English is the official working language.
No one common language is spoken on the Indian subcontinent, except Hindi and English which are the co-official national languages of India. Both languages are used as lingua franca all over the various linguistic regions.
For many of the educated Indians, English is virtually their first language. Most Indians, however, are multi-lingual and it is only their second language.
Hindi and Urdu
Hindi and Urdu are actually slightly different dialects of the same language. Their main difference lies in their vocabulary roots, scripts and religious backgrounds.
Hindi vocabulary mainly comes from Sanskrit. It is written in Devanagari (a script form) and spoken mainly by Hindus. Hindi itself has two major varieties: western and eastern Hindi. Both are spoken by more than 400 million people.
Urdu has words with Persian and Arabic origins, and written in Persian-Arabic script. Urdu is spoken by Muslims in India and in Pakistan.
All the Indian languages belong themselves to two major linguistic families: the Indo-European and Dravidian groups. The others come from Austro-Asiatic and Tibeto-Burman groups and other small isolated languages. The Indo-Aryan group (part of the Indo-European family) is spoken by about 74% of the population. The Dravidian is spoken by around 24%.
Bengali
Another major language is the Bengali. It is spoken by almost the entire population of Bangladesh, and in West Bengal. Bengali is the language of the Indian poet, the Nobel Prize winner Rabindranath Tagore. Like Hindi, it is also descended from Sanskrit and has the most extensive literature of any modern Indian language.
It has around 200 million speakers and developed as a language in the 13th century.
Punjabi
Punjabi is spoken in the Punjab region which covers parts of northeastern India and western Pakistan. It is often referred to as the language of the gurus, the founders of the Sikh religion. The secret teachings of Sikhism are in Punjabi. Punjabi is close to the Hindi language.
All in all, these are the major languages in use in India. Each one has a number of speakers that run into millions, some of them, more than the population of an average-sized country. Learning an Indian language is one intimidating work but a real satisfying one, considering that each one has a culture that is as rich as any countrys.