<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by NickyD:
I meant a specific fare code such as a travel agent would use. I'm just trying to learn the best methods of booking travel... I've noticed that different fares use different fare codes, and was wondering how they worked.
Thanks,
Nick.</font>
Generally, there are 4 main fares of interest to you.
L/U - Non-upgradeable but cheapest
Y - Fully upgradeable and fully refundable
F - F/C and fully refundable
K,H,Q,M,B and others - Upgradeable but may not be as cheap as L/U.
That said, the above post has a link to the Delta Flyer's Guide. It has some terrific stuff which is worth the visit. Many of your questions may be answered there.