दौड़ती है हिमालय तट से सागर, हमसफ़र हर राह पर, हवाई जहाज़ों को त्याग कर, करो अक्सर, भारतीय रेल में सफर. - Arpit P

MEANS
Rajdhani - Inter-city fully air-conditioned superfast trains connecting the national capital, New Delhi with major metropolitan cities
Duronto - Non-stop point-to-point trains connecting major Indian cities
Sampark Kranti - Superfast trains that provide almost non-stop connectivity between States and the national capital, New Delhi
Shatapdi...
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- Inter-city fully air-conditioned superfast trains connecting major Indian cities
Garib Rath - Fast fully air-conditioned trains subsidized for poor people
Jan Shatapdi - Inter-city superfast trains connecting major metropolitan cities, with low-priced accommodations. These trains can be considered a 'down-scale' version of Shatabdi trains.
Superfast - SuperFast Mail/Express trains making multiple stops
Mail/Exp - Regular Mail/Express trains making multiple stops