There are (normally) three different cabin/service classes:

Y = Economy
C = Business
F = First

Each of these three classes contain different booking classes which can vary between different airlines.
For example SAS, which doesn't have any first class, uses the following.

http://www.sas.se/en/EuroBonus/Earn-...nes/SAS/Chart/

And for Lufthansa the booking classes / earnings are as follows.

https://www.miles-and-more.com/onlin...40&cid=1000261

The big letter printed on LH:s boarding pass is normally the cabin class, meaning either Y, C or F (LH also uses M for Economy if I remember correctly).
While the one on your itinerary is the real booking class. (You should also be able to find this on the boarding pass)

Then again, if you wanna know for example how many Eurobonus point you will earn on a LH flight, you need to look it up from the Eurobonus pages.
http://www.sas.se/eurobonus/tjana-po...lag/Lufthansa/