While booking ticket with railway's, i used to see WL (waiting list),RLWL(Remote Location waiting list),FWL ( Full waiting list)....etc
What is the meaning of these .......
Reservation Against Cancellation ('RAC') refers to a ticket status where you have requested a reservation for a berth but do not actually have a reservation for a berth until some berth becomes available through the cancellation of some other reserved ticket. RAC ticket holders can board the reserved coach for the overnight journey, but are only assured of reserved sitting accommodation on the seats at the side of the coach (not in the compartments). If no berths become available, two RAC ticket holders have to share the seats on the side without converting it to a berth by laying down the bunk over them. A third RAC ticket holder gets to use the upper side berth. The side berths are shorter than the berths in the main compartments.
Tickets on the Wait List ('WL') are not even guaranteed such sitting accommodation, and are entirely unconfirmed at the time of issue. Seating or sleeping accommodation will be available only if enough other persons with reservations cancel their tickets. On some popular routes, high wait-list numbers in the hundreds are not unusual, and holders of such tickets may still end up with reserved accommodation by the day of the journey since there is a lot of flux as people cancel and re-arrange their trips.
For many trains it is not unusual to see high numbers for the waitlist positions, such as in the 300s. For some trains, this is still reasonable because the trains typically see a lot of cancellation and re-booking activity in the days just before the journey. For some other trains, the high numbers on the wait list indicating that such requests for reservations are still being accepted may simply mean that the zonal railway is planning to run an additional trains as specials to clear the rush later. When the maximum wait list number defined for a train is reached for a particular day's journey, the reservation system refuses to accept any more requests for that day. In such cases, this is shown as 'REGRET' in the reservation status.
The reservation status for a train is shown online in a format such as 24-4-2005 WL 273 / WL 189. This indicates that earlier the position was a wait list of 273, and now the wait list has shrunk to 189; i.e., if you were to try to book a ticket now, you would get a wait list position higher than 189. A notation such as 24-4-2005 REGRET / WL 215 indicates that earlier no reservations were being accepted even on the wait list, and now the wait list position is at 215.
Most waitlisted tickets are issued by the originating station of a route. Stations close to the originating station may also share the same wait list (e.g., Chennai Egmore, Mambalam, Tambaram, Chengalput all share wait lists and reservation quotas with Chennai Central). This waitlist is the General Waiting List or simply Waiting List (WL).
The number of tickets that can be issued in total for travel from the originating station, issued by booking offices of the originating station and other nearby stations is known as the General Quota (somewhat unintuitively abbreviated 'GN'). Smaller intermediate stations that do not participate in the networked computerized reservation system issue tickets from specific quotas, known as Remote Location Quotas ('RLQ') and Road Side Quotas ('RS'), and these quotas can themselves have wait lists.
A Pooled Quota Waiting List ('PQWL') is shared by several small stations in a particular region. E.g., Tiruppur, Salem, etc., share in the quota and wait list for some trains originating from Trivandrum or Mangalore. As another example, the 2723 Andhra Pradesh Exp. has three quotas, for Secunderabad - New Delhi, Secunderabad - nagpur, and Secunderabad - Bhopal. There is also a pooled quota for passengers travelling from Secunderabad to stations beyond Bhopal but short of Jhansi. If this quota is exhausted, a passenger is placed in the pooled quota waiting list. Pooled Quotas normally operate only from the originating station of a route, and there is only one Pooled Quota for the entire run. The Pooled Quota is intended to be utilized by passengers travelling from the originating station to a station short of the terminating station, or from an intermediate station to the terminating station, or between two intermediate stations. Such remote location quotas are also provided when there is a very strong demand for the train in question, because of which, without such additional quotas, all seats or berths might be fully consumed by passengers from the originating station leaving nothing available for those wishing to travel from intermediate points. Vacant Pooled Quota berths are automatically tapped by the PRS for booking end-to-end passengers. Passengers in the Pooled Quota Waiting List are cleared against the vacancies in the earmarked Pooled Quota only, or against General Quota vacancies available at the time of charting.
A Running Line Waiting List ('RLWL'), also known as Remote Location Waiting List or Road-Side Location Waiting List applies to the quotas of specific intermediate ticketing stations on a route, known as the Remote Location Quota. E.g., Solapur has a quota with a corresponding wait list on the Mumbai - Chennai mail). The intermediate stations are usually the more important towns or cities on the route. The RL quota takes care of passengers travelling from these intermediate stations up to or short of the terminating station. RL quota tickets are never available from the originating station of the route. When the RL quota is exhausted, RAC (Reservation against Cancellation) begins, and it is then followed by ticketing on the RL Waiting List; in some cases when the RL Quota is small, the RL Waiting List is active immediately. There can be more than one Remote Location Quota for some long distance trains, corresponding to different stations en route. Passengers in the Remote Location Quota Waiting List are cleared against the vacancies in the earmarked Pooled Quota only, or against General Quota vacancies available at the time of charting.
In some cases if a ticket is to be booked from an intermediate station to another intermediate station, and is not covered by the general quota nor by the remote location quotas or pooled quota, the request for the ticket may go into a Request Waiting List ('RQWL'). A ticket on this list is usually confirmed only when there is a confirmed ticket for a passenger travelling from the originating station to that intermediate station, although in the case of some Rajdhani routes and other long-distance trains specific quotas may be earmarked for use by passengers on the RQWL, for some intermediate stations. Tickets for travel from an intermediate point to the terminating station are also handled in the same way if there is no Remote Location Quota defined for that intermediate point.
For road-side station quotas, berths or seats are booked by the originating station for journeys up to the road-side station and distance restrictions may not apply. If berths or seats are redefined from a remote location, then booking can be done beyond the road-side station, within the limits for the remote location's quota. In no case, however, will through passengers be booked on multiple quotas, e.g., partway on the general quota of the originating station and the rest of the journey on a remote location quota.
Other Quotas: There are several kinds of quotas for tickets for various special categories of passengers, other than the quotas for intermediate stations mentioned above, ticket agencies in other towns ('OS' = Out-Station quota), etc. These include small numbers of seats and berths set aside for railway officials ('HO' = Head Office quota ('High Official' quota)), ministers and high bureaucrats as well as members of parliament and their staff ('PH' quota ('Parliament House')), defence officials ('DF' quota), foreign tourists ('FT' = Foreign Tourist), handicapped travellers ('HP' = Handicapped Person), railway staff on duty ('DP' = Duty Pass) (this has its own waiting list, the 'DPWL' or Duty Pass Waiting List, especially for railway staff travelling on Privilege Passes on Rajdhani trains), women travellers ('LD' or 'LQ' = Ladies Quota), and those needing to travel for extremely urgent reasons ('EQ' = Emergency Quota), etc. Each one of these quotas can theoretically also have its own waiting list, usually denoted by the quota abbreviation followed by 'WL', e.g., FTWL, EQWL, HPWL, etc. RAC or Reservation Against Cancellation (see above) is technically not a quota, but is often shown as one, as 'RC' quota.
Tatkal Scheme: For a surcharge, which varies depending on the class of travel, it is possible to reserve accommodations for a rail trip just 1 to 5 days before the start of the journey, even if the normal reservation quotas are fully booked. The Tatkal scheme originally allowed booking a ticket just 1 day in advance of the journey but this was later changed to 3 and then to 5 days in advance - and subsequently shortened  to 2 days. (Please check the current rules.) An identification document should be shown during reservation and the same document carried on the journey and produced on demand, a measure to foil the re-sale of reserved tickets. This scheme was introduced by IR as a measure against travel agents and touts monopolizing reserved tickets, and to allow for emergency travel on busy sections. Tatkal reservations come out of a Tatkal Quota (code 'CK', with waiting list 'CKWL'), although in some cases 'TQ' has been seen in reference to this. Concessional tickets are not allowed under the Tatkal Quota, nor are Senior Citizen passes. The complete end-to-end charges for the journey are collected in addition to the Tatkal surcharge, even if the passenger intends to board the train at an intermediate station. (This may have changed  and the correct partial fare for the journey may be payable now.) In some cases, Tatkal quota fares are charged at Peak Period rates even if travel is during non-peak periods. The Tatkal scheme was originally introduced for selected trains, and for end-to-end travel only, but has now been extended to all trains where reservations are available and for partial journeys as well. The Tatkal booking period was originally 1 day in advance of the departure date, but was later extended successively to 3 and then 5 days. At the beginning of the scheme, the Tatkal Quota allowed for 72 berths in SL, 6 berths per coach in 3A, 4 berths per coach in 2A, and 6 seats per coach in CC, but the quota has been greatly expanded in recent years . The Tatkal Quota is higher on the weekends than on weekdays for most trains. Vacant berths in the Tatkal Quota are used for clearing General RAC and WL passengers.