Only those on bona fide tourist visits should apply for tourist visas. A Tourist visa cannot be used for any other purpose such as business, education, research, writing articles, social work etc. A Tourist visa should not be applied for, if the purpose of visit falls under any of these categories. Tourist visa is non-convertible. Tourist visas are generally issued for a maximunm period of six months and under special circumstances for one year but validity of visa will conform to the period requested. A Tourist visa is non-extendable. Long term tourist visa is normally issued to travel agents who have to visit India frequently and need embassy's prior approval. Double or triple entry Tourist visa is possible only if you attach a copy of your flight reservations/itineary for all the trips.
Information for those visiting India on Tourist visa
Those with such visas will also need to register with the Foreigners Regional Registration Office (FRRO) in case they stay continuously in India for more than 180 days. Those with six month multi-entry visas do not have to register with the FRRO.