What is TKWL, CKWL, RAC, PQWL,GNWL, RLWL,CNF etc. ?

RAC means Reservation against Cancellation. If you have a RAC ticket, then your travel with a train is guaranteed but you will be given a seat (half of a side lower berth mostly) to sit and travel not an entire berth.

GNWL General Waiting List wait-listed tickets are issued to the passenger who begins his/her journey from the originating station of a route or stations closer to the originating station.

PQWL Pooled Quota Waiting List is shared by several small stations of a train route.

RLWL Remote Location Waiting List ticket is issued for the stations between the originating and terminating stations.

TQWL Tatkal Quota Waiting List was earlier CKWL. It is the waiting list tickets booked under Tatkal Quota.

CNF stands for "Confirmed". The PNR status of the train ticket that shows CNF means that the seats are confirmed.

From: Train Platform Locator

CNF means your seat is Confirmed

RAC is Reservation Against Cancellation. RAC means that you will get a seat but you will have to share it with someone else. There are chances that your RAC ticket can get converted into a confirmed ticket.

GNWL is General Waiting List. Waitlisted tickets are issued when all the seats are filled and the passenger begins his/her journey at the originating station of a route or stations close to the originating station. This is the most common type of waiting list and has got the highest chances of confirmation. It gets automatically canceled on chart preparation & Refund will be automatically credited to Bank Account in 3 to 7 days.

PQWL is Pooled Quota Waiting List. It is shared by several small stations. The Pooled Quota is generally allotted for passengers traveling from the originating station to a station short of the terminating station, or from an intermediate station to the terminating station.

RLWL is  Remote Location Waiting List. This ticket is issued for intermediate stations between the originating and terminating stations as these are the most important towns or cities on that particular route.

RQWL is Request Waiting List. If a ticket is to be booked from an intermediate station to another intermediate station, and if it is not covered by the general quota or by the remote location quotas or pooled quota, the request for the ticket may go into a Request Waiting List (RQWL).

TQWL or CKWL is Tatkal Waiting List. For tatkal tickets, the waiting list issued is TQWL. If tatkal ticket goes up, it directly gets confirmed and doesn’t go through RAC status, unlike GNWL. During chart preparation, general waiting list (GNWL) is preferred over tatkal waiting list (CKWL) therefore tatkal waitlisted tickets are less likely to get confirmed.