the down & dirty version
http://www.air-ticket.us/info/airlin...breviation.php
The full fare economy can get really pricey, yes. I subscribe to First Class Flier - you might want to check out a free trial issue since they have some great 'swap' tables for various carriers. For example, a business class seat from IAD to MUC might run $2,500 or you can get a discounted fare economy seat from $1,200 then buy 25,000 miles from United @ $300 and upgrade yourself for a lot less. Those are just numbers I made up but you get the idea. Or, if you use Amex see if you can buy upgrade points through them and then use on a particular carrier. Definitely shop around online and you'll probably come up with decent deals.