Classes of Passengers

[SLF 999]

Forgive my ignorance but can someone please tell me what the classes of passengers are I see in other threads, I understand club, first , eccomomy etc, but what is Y , D , C etc?
Thanks

[Gaza]

Airlines have different booking class within travel classes. These normally correspond to the fare paid. For example:-

First Class is normally booked in F, discounted First Class is booked in A or occasionally I
Business Class is J (long haul) or C (short haul). Discounted business is normally booked in D.
Premium Economy is normally booked in W or T class
Full fare Economy Class is normally booked in Y. Discounted economy with varying restrictions on changes, cancellation penalties, etc are booked in classes such as V, B, etc.