Everyone is a gangster (Rajdhani, Shatabdi, Tejas) until the real Gangsta (Vande Bharat) walks in 😂 - Mushfique Khalid

A very quick explanation of RAC
WL = Waitlist RAC = Reservation against cancellation
An RAC ticket gets you on the train (A WL ticket doesn’t) and in your chosen class, but there’s a chance you could end up with just a seat. (very unlikely if you book early)
A berth is split into 2 seats for 2 RAC ticket holders, if there’s...
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any last minute cancellations, or if any quota allocations remain unsold, or if any confirmed ticket holders are given a free upgrade (more later), an RAC ticket holder is given the empty berth, the other RAC ticket holder can then convert the 2 seats into a berth.
RAC tickets are only issued for 2-tier air con (4 seats per carriage), 3-tier air con (6 seats per carriage), non air con First Class (4 seats per carriage), and non air con Sleeper Class (up to 12 seats per carriage).
How do RAC and Waitlists all work?
When all the available seats/berths in an individual train/class have been sold, the railways start selling RAC tickets (2A, 3A, FC & SL only), when all the RAC tickets have been sold, then a waitlist is started for all the train classes, and you’re sold a waitlisted ticket.
As people cancel tickets, a RAC/WL ticket will move closer to a confirmed berth. Also, when the final reservation chart is prepared, any un-sold quota berths will be used to reduce the RAC/waitlist.
Tickets will be sold in the following order....(4 RAC places in this example)
Available 02
Available 01
RAC 01
RAC 02
RAC 03
RAC 04
WL 01
WL 02