National Youth Day is celebrated in India on 12 January on the birthday of Swami Vivekananda. In 1984, the Government of India declared and decided to observe the birthday of Swami Vivekananda (12 January, according to the English calendar) as a National Youth Day every year from 1985 onwards. To quote from the Government of India's communication, 'it was felt that the philosophy of Swamiji and the ideals for which he lived and worked could be a great source of inspiration for the Indian Youth.'
Swami Vivekananda's birthday (12th January, 1863), according to the Indian Almanac (Vishuddha Siddhanta Almanac) is on Pausha Krishna Saptami tithi, which falls on different dates in the English Calendar every year (generally in the month of January). This is observed in various centres of Ramakrishna Math and Mission in a traditional Hindu manner which includes mangalarati (a kind of worship practised in India, specially by Hindu people), special worship, homa (fire-ritual), meditation, devotional songs, religious discourses and sandhyarati (vesper service at evenings).
(... from Wikipedia on 2012-04-17 23:04:22)