There are a lot of languages spoken in India. Hindi is one of the major languages spoken out of 18 major languages and 1600 regional dialects; some of the major languages are Hindi, English, Assamese, Bengali, Gujarati, Kannada, Kashmiri, Malayalam, Marathi, Oriya, Punjabi, Sanskrit, Tamil, Telugu and Urdu. (This sentence is basically copy and pasted because it is just a list). Even Hindi which is widely spoken not everyone in India recognizes it, only about half of the population speaks Hindi. Hindi is the third most widely spoken language after English and Mandarin; about 500 to 600 million people speak Hindi in the world. Hindi is closely related to Urdu. Hindi and Urdu is both descended from Hindustani which is the language spoken in Delhi and Northern India at about the ninth and tenth centuries. Hindi has been influenced by Persian, Turkish, Farsi, Arabic, Portuguese, and English; Hindi has been mixed and broken because of immigrants from other places. There are too many languages in India that the central government won’t understand all of it. The only languages they recognizes are Hindi, Urdu, Bengali, Nepali, English and a FEW and few as in really only a few more out of the ton of languages. Most of Hindi came from Sanskrit loan words that had been changed. Hindi finally started to become the national language during the colonial period. From the eighteenth century Hindi began to grow a lot and is gaining more power in India. Hindi is written in the Devangari script and Urdu is written with the Perso-Arabic script. Hindi is now used all over the place and is continuing gaining power all over the world. Hindi might someday become be used more than English or Mandarin, who knows? All we can do is look at what will change in the next few hundred years.
If you are thinking of going to India all you have to know is pretty much english and some Hindi so you can tell the person who you're talking to that you don't know Hindi well. English is the secong major language after Hindi is India so most of the people do know haow to speak english but it will still be better.
Knowing some Hindi phrases are important in order to communicate.
You kight want to know the numbers so you can tell the quantity you want for something.
You might want to know the alphabets iin order to say some harder words and to read something.
You will want to know some Urdu because it is one of the major languages.
The most important of all, you must know ENGLISH!