Lets tell you my experience in metro when I was n Delhi for about two years, when I visited first time delhi I heard lot about this metro but when I saw the trains, station & got stunned for a moment, i have seen such things in Hollywood movies, NGC & in TV programmes of other countries & felt India is really developing.
there are 4 different lanes in Delhi metro(Blue, yellow, green & red) & two junctions Connaught place(CP) & kashmiri gate where you can change trains.there are many ticket counters , you wont feel crowded near ticket counters & the best facility is SMARTCARD (which will look like your ATM Card but now its been changed to a key chain ) you have to buy it by depositing 50 Rs it will not contain any balance & you have to recharge it in counter with the desired amount. When you want to board a train you have to swipe it at swipe counters then only you are able to board train & to tell you about platform its painted where the coaches door will be when train stops.
Coaches are sealed for air cooling purpose & speakers to inform which station is ahead & which side doors will open in next station & all general & warning messages.
One thing I loved the most is the construction work of metro is so rapid & clean you cant believe the road on which we travel beneath that metro runs, one who visits Delhi for first time they feel proud about india that its developing.