India is a free country well almost. If you have your essentials right things wok out better. After the incidence of extremism in the country keeping your identity intact is of utmost importance. What I mean is that you should have documents to prove who you are. Your countenance and you yourself has no validity until unless you have been certified by external source who you are.
The identity subscribes to not only you but your residential proof as well. You cannot go about carrying sales deed of your apartment or bunglow so thankfully the address is certified as well. You photo is also a way to prove who you are but it should be attached to the identity proof that you carry.
This travel essential is a prerequisite during train travel, air journey, booking a hotels or for transactions in the bank. For inbound travelers the passport works under most circumstances but the original is required often so please carry it wherever you travel in India. Be careful of pick pockets and thieves who are interested in your purse or money bag but the passport is the causality as well since they are tied together.
For residents driving liscene is most handy since any way people carry it with them always. The other is the Pan Card issued by the Income Tax Department in the country. The recent addition is Addhaar Card also called UID Card issued by Unique Identification Authority of India. Both of UID Card and Pan Card can be obtained online through an application. The status check can also be done online by those in hurry to receive one.
Lot many other things like electricity bill or telephone bills will work but a certfied image is a must. Not only in hotels but even in cyber cafes all across the country an identity proof is required though your mobile number may also work as last resource.