jan shatabdi is different category of trains providing-
1.faster point to point inter city connections
2.had catering facility when introduced, now removed
3.no telescopic fare facility unlike intercity trains which helps you save money
4.seats...
more... are a bit more comfortable than intercity
5.price is quite high when compared to intercity trains
6.fully reserved train. No unreserved coaches. Though tickets are issued from unreserved counters if seats remain empty after charting