RailFanning is an art-form; RailFans are the paints - Ayush Kumar Singh

i-ticket: You can book an i ticket only if there is a 2-day gap between the booking date and the travel date. This is to allow time for the ticket to be couriered to you. The ticket will be couriered to either one of the addresses that you have specified while you registered on irctc website, or to any other address you specify at the time of booking. There is no option currently to change the name of the recipient - it will be sent in your name. You can book an i-ticket even if the status is 'waiting list' (as opposed to 'confirmed' and 'RAC').THESE R IN SELECTED CITIES ONLY .
e-ticket: If you book an e-ticket, no ticket will be...
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couriered to you. Instead, you need to take a print of the ticket that appears on the website after you book it. While booking, you will be required to provide some details of a personal identification document (like driving licence number, passport number etc) and you MUST carry this identification document along with your printed ticket when you travel. E-TICKET CAN BE BOOKED FROM ANY WHERE IN INDIA OR ABROAD.