GNWL = General quota waitlist
The General quota is for passengers travelling the full length (or most of the way) of the train's journey, and the General quota is usually the largest quota.
RLWL = Remote Location quota waitlist
On long distance trains, some stations along the route will be designated Remote Location stations, these will be big stations, and mostly where the train...
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will call at the chosen station (and at the destination station) at popular times, it may also be a station that many people will book to (from the originating station), and this can mean that many seats/berths will become available at the remote location station.
Remote Location stations prepare their own reservation chart 2-4 hours before the train is due to arrive/depart from that station, or the evening before in the case of late/very early departures.
RQWL = Request Quota waitlist
Let me give an example (and this is off the top of my head, so unlikely to be a real example).
Let’s say that Dound Jn is allowed 2 Sleeper Class berths on the Mumbai-Bangalore Udyan Express, and these berths are booked, the next person who wants to travel to Bangalore on the same train has to join a Request Quota waitlist, this waitlist will only improve if a person books a Mumbai-Dound ticket from one of the larger quotas, this would leave the seat vacant from Daund, so would allow another person to board at Dound.
So in theory, the person is requesting a berth in case anyone happens to be getting off at Dound.
(the ‘ping’ from the microwave oven tells me my sticky toffee pudding is ready, damn, it’s too hot, I’ll leave it for 10 minutes to cool down)
PQWL = Pooled Quota waitlist
Pooled Quota is basically anything not covered by the other quotas, though the General ad Remote Location quotas take up most berths. (and lately the Tatkal quota).
Pooled quota can include (though not always) Originating station to intermediate station, Intermediate to intermediate, and intermediate to destination station (though it would be separate from remote location quotas).
CKWL = Tatkal quota waitlist
Tatkal quota is just for last chance bookings and in most cases, can only be booked from originating station to destination station, though you can change the boarding station.
(a strange noise draws me to the kitchen, the noise gets louder as I get nearer, "eat me", "eat me", "eat me", it seems to be coming from my sticky toffee pudding )
How fast will the waitlist move?
It’s not easy to predict, and can be different for every train, even trains on the same route.
The first thing a person needs to find out is how many berths are used for that class on that train between the 2 selected stations, to do this, a person needs to check availability for 90 days ahead.
GNWL = General quota waitlist
I’d be unlikely to accept a waitlisted ticket that’s more than 25-30% of the total general quota, even 90 days ahead, and as the time goes down, the acceptable waitlist number comes down, though 10% of the total general quota can still be good even a week before the train.
RLWL = Remote Location quota waitlist
Same as general quota, but total berths available is likely to be a lot less.
RQWL = Request Quota waitlist
It really depends on the train, and the total number of berths used, but in most cases, I probably wouldn’t want a waitlisted ticket.
PQWL = Pooled Quota waitlist
Total berths used for EXACT same train, class and pair of stations is essential info for the pooled quota waitlist, it can be as low as 2 berths, so even a PQWL 1 ticket would be very unlikely to become confirmed, a very tricky waitlist to predict, so a waitlist that’s best avoided in most cases.
CKWL = Tatkal quota waitlist
Always tricky, mainly because the tickets are booked only 1 day before the train will depart, and because the cancellation fees for confirmed tickets are higher than other quotas, so there’s less chance of cancellations, also, there’s no other quotas (foreign tourist quota , VIP quota , Military quota etc.) can come to the rescue of waitlisted passengers (if quotas remain unsold).

PQWL:
A group of intermediate stations form a cluster/pool to form a quota.
1) Start-End Quota.
2) A single Wait list maintained across the route of the train
3) Since it is a start-end quota,...
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it can be applicable across any journey combination of the train, meaning for a journey leg applicable for GN/RS/RL, berths for the same can also be given from PQ.
In this case, the PNR usually needs to have more than one passenger.
If the original quota runs in WL, or doesnt has sufficient number of confirmed berths available, then PQ is used in this case.
For ex:
Pass 1 (Confirmed, PQ)
Pass 2 (Confirmed, PQ)
Pass 3 (Confirmed, GN)
Pass 4 (Confirmed, GNWL)
Note: The journey leg here comes under GNWL. Due to the unavailability of sufficient number of confirmed berths, the first two passengers are confirmed against PQ, third against GN and then the concerned Waitlist applicable across the journey leg commences.
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However in rare occasions, PNR having single passenger are also placed against PQ in the same way.
4) Some of the stations forming PQ, are often given a share of their own. Thus either the common quota across all the PQ is first utilised and then the individual quota of the stations and/or vice versa.
Due to the above reason, most of the time you would find cases like:
Pass 1 (Confirmed, PQ)
Pass 2 (WL 56, PQ)
Here, the first pass was confirmed against the individual quota of the originating station and/or confirmed berths available for that specific journey leg and the second passenger was placed in the common Waitlist applicable from start-end.
Another reason for the above to happen may be attributed to #berthmultiplexing
5) Charting of the same happens at the originating station (Reason : Point 1)
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RL Quota:
Assume when a quota is defined from Mumbai to Solapur, its NOT "Mumbai RS quota", it is "SOLAPUR RS quota".
Note :
RS quotas are identified as to where they end
RL quotas are identified as to from where they start
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RSWL:
RSWL= Same as RQWL.
1) Start-Intermediate Quota.
2) A constituent of the Remote Quota group. In this case, takes place when the intermediate station does not have a share of the quota from the originating station; i.e. GNWL. Thus making the relative quota small.
3) Confirmed tickets are issued from GNWL. For combined tickets (Having more than one people in a PNR), confirmed berths can also be given from Pooled Quota. (Depends on availability).
After the confirmed berths are exhausted, most of the times it directly moves to WL.
4) Moves slowly, supports RAC. Becomes handy when the train do not support PQWL.
5) To avoid landing up in RSWL, always check for stations beyond your preferred destination station supporting GNWL.
6) RSWL is usually followed by RLWL. Most of the times RLWL is not visible due to distance restriction and/or restricted booking/s.
7) Because of the above reason, confirmation chances of RSWL in Rajdhanis is pretty low or rather uncertain. Since the system would not allow booking for the latter part of the journey, it prefers to clear the GNWL booked from start-end.
8) A train can support more than one RSWL.
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RLGN/RLWL== it is the same as RLGN.
When you purchase a ticket from PRS, it would be depicted as RLWL, and upon checking the PNR online it would be shown as RLGN.
Some months back I had seen specific quota depicted as RLWL but guess the said process has been discontinued now.
1) RLGN is intermediate-end quota.
2) Has a share of the general quota/originating station= Has more number of berths= Supports RAC.
For some trains, the quota of the intermediate stations is quite low and hence it does not support RAC. In these cases, it is usually depicted as RLWL = Does not support RAC and hence has least chances of confirmation. (However as said earlier, to a lot of people RLGN and RLWL is one and the same. Hence you would need to search whether the station holding this quota has a larger share of it or just a nominal one)
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As said by MST Sir here:
/blog/post/30023/6
Assume in Coimbatore Kurla Exp, some berths can be reserved only between Coimbatore and Bangalore. This is called Road side quota (RS quota : start to intermediate).
Some berths (infact the same berths) can be reserved only between Bangalore and Kurla. This is called Remote Location quota (RL quota : intermediate to end).
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The berths on charts pasted on trains are denoted as "SBC/" and "/SBC" respectively. One cannot book a single berth in these quotas from anywhere in CBE-SBC section to SBC-LTT section. The system does not allow this, neither at booking time, nor at charting time. If some one has to overcome this issue, he needs to book 2 tickets, one upto SBC and other from SBC, to be eligible for these quotas.
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For RLGN, since it shares a part of the originating station, confirmed berths are given from the General Quota and sometimes from the Pooled Quota(Kindly go through the explanation of Pooled Quota)
Pass 1 (Confirmed, GN)
Pass 2 (Confirrmed, GN)
Pass 3 (Confirmed, PQ)
Pass 4 (WL 1, RLGN)
To end the discussion, kindly note Remote Quotas are not actually quotas but are Waitlist.
Confirmed berths for all of the Remote Quotas are given from the General Quota and sometime from Pooled Quota as explained in the earlier posts. Cancellation of the Remote Quota Waitlist's happens very slow. Hence it is always advisable to be placed against GNWL.

Let us assume there is a Cricket Match to be played in your city. Your office has been provided with 200 passes whereas you have 20 senior officers and 240 deputy officers/clerks.
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1. Now the senior level officers are provided with the priviledge of watching the match end-end. They would not have to share their tickets with anyone else. (20 tickets FOR 20 officials).
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2. Since there are remaining 240 officers with only 180 remaining tickets, the office has decided to share one single tickets with different time SLOTS.
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3. The slots are as follows:
a) 9-12
b) 1-3
c) 4-6
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4) Now there are only 180 passes left. How to share 180 passes for 240 people?
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5) Slot (b) has a maximum demand due to which the office decided to PROVIDE 100 passes for the said time slot and divide the remaining 80 seats into the other two slots (40 seats each)
6) As per first-cum-first serve basis, these seats are now being filled up.
40 Confirmed Seats for Slot (a)
100 Confirmed Seats for Slot (b)
40 Confirmed Seats for Slot (a)
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7) The remaining officers {240-(40+100+40)}=60 people are allocated waitlisted position as per their wish with 25 people in the first slot, 15 people in the second and 20 in the third.
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8) The movement of these waitlisted people shall primarily depend upon the cancellation of the already confirmed tickets in the respective slots.
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9) Now, if I assume a total of 120 seats were allocated to both the three time slots (a), (b) and (c) with no specific division.
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10) It may so happen 30 people books for slot (a), 40 for slot (b) and 50 for slot (c) the same 30 seats would not go vacant for slot (b) and (c) and at the same time the 40 tickets would not be left vacant for slot (a) and (c) and again at the same time the 50 seats shall not remain empty for slot (a) and (b). Total utilisation has to be done.
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11) Thus, if I assume that out of the remaining (240-120=120) officers are left and 50 books waitlisted tickets for slot(a) and 40 books waitlisted tickets for slot(b) and 30 waitlisted passengers for slot (c) all of them would be given confirmation; even though no actual cancellation ticket has taken place for the individual slots. (Utilisation of vacant berths/Confirmation at source)
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12) If there was only one waitlisted passenger who wanted to view the entire show and simultaneously one confirmed tickets each were cancelled for all the slots respectively, the waitlisted passenger shall not be given confirmation. (Merging of sectorial quota/berths never take place.
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13) However, if one berth from the senior officer quota gets CANCELLED, i.e. vacancy exists for this quota, the above may get confirmation if he wants to book for the entire show. If any subsequent ticket is booked for slot(a) or slot (b) he would directly land up at the then prevailing waitlisted position; i.e. WL 26 or WL 16 (Refer Point 7)
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1=> FOR=> GNWL
2=> SLOTS=> PQWL
3=> Stations(Charting) within the Pooled Quota.
5=> PROVIDE=> Individual Quota allotted. Higher than other stations.
7=> Waitlisted Tickets
8=> Confirmation based on cancellation of confirmed tickets against respectively slots (journey legs)
9=> Start-end Pooles Quota
11=> Forwarding of berths=> Confirmation through charting at originating station/previous remote station
12=> Merging never takes place
13=> Confirmed berth can be issued from General Quota, based on availability.
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Kindly note that PQ exists from start-end. Even though in the first example, I have not showed start-end Pooled Quota, do not get confused. Apart from the start-end quota, some specific Pooled Stations are allotted individual quota of its own. Confirmation do not always depend upon cancellation of confirmed berths. It also depends upon forwarding of berths/quota.