Both are waiting lists, but they apply to different booking types:
GNWL — General Waiting List
- For passengers boarding at the train's origin or a major boarding point.
- Highest priority. Cleared first when seats free up.
- Best confirmation chance.
PQWL — Pooled Quota Waiting List
- For short-distance bookings between intermediate stations (not origin → destination).
- A small pool of seats is shared across multiple intermediate journeys.
- Confirms slower; lower chance than GNWL.
If you have a choice, prefer booking from an origin station or earlier major halt to get GNWL.