First Indian Railway train was run in 1853 between Mumbai and Thane. Mumbai and Thane are western coastal districts of Maharashtra. Current Indian Railway trains are the result of gradual development in technology. Today it runs thousands of daily express and local passenger trains. Railway has categorized these trains according to their average speed and number of halts on their route. Below are the list of train types:
Metro Trains: These trains are equipped with latest technologies and facilities. It currently runs in few metro cities of India like Mumbai, Delhi and Kolkata. Such metro trains are in demand and government had planned its expansion in other metro cities as well. Metro Rail tickets do not generate unique PNR number because one can not reserve a seat in these trains. These are moderate in speed and generally runs on their scheduled time.
Suburban Locals: They run only in few big Indian cities like Mumbai, Kolkata and Chennai. These are also examples of trains for which seat reservation is not possible and hence one can not get pnr status for tickets. These are further divided into slow locals and fast locals. Slow locals halt on every station while the fast ones halt only on main important stations.
Passenger Trains: Passenger trains can also be further classified into slow and fast passenger trains. They run between important small distanced cities.Slow passenger trains have stoppage at every single station in between their route. Reserved tickets are not available and hence unique pnr number generation is not done for tickets.
Express & Super-fast Express: These trains are relatively faster than the above mentioned. They run across long distances and one can book a reserve ticket in these trains. As tickets are reserved, booking system generates unique ten digit pnr number on each tickets to identify the traveler. PNR status checking facility are made available for non reserved train tickets.
Shatabdi and Janshatabdi Express Trains: These are high speed trains available in Indian Railway to connect moderate distanced important stations. They do not have sleeper coaches. They only contain seats for seating. Main difference between Shatabdi and Janshatabdi trains is that Janshatabdi trains have both AC and non AC coaches while Shatabdi trains are fully air-conditioned. Seats can be reserved and pnr status can be checked.
Garib Rath: These trains have AC 3 tier coaches and ticket price is relatively lower than the other air conditioned trains. One can check pnr status of Garib Rath at trainspnrstatus.com
Rajdhani Express: These are fully air conditioned trains and connects major cities of India. They are high priority trains and generally runs on their scheduled time. They have very few stoppage in between their route. Seat reservation facility is available in these trains. One can check Rajdhani Express pnr status on this website.
Duranto Express: These are source to destination train service started recently by Indian Railway. From source to destination means, these trains do not stop on any station that comes in their route