Font replacement mechanism

[Roland Turcan]

Hello ubuntu-users at lists.ubuntu.com!

Could someone help me with understanding of font replacement
mechanism, because I cannot get rid of this subject for longer time.

I maintenance/develop application in Kylix3/Qt2.3 and fonts are
sometimes strange. For keeping it easier I use only adobe-helvetica
and courier fonts, but still many customers report, that application
doesn't show fonts correctly. Even printer prints often (which is
bigger problem) different fonts than they are set by the application.
This problem with screen and printer is present separately or together
and it must be in relation to font replacement mechanism.

Where can I find any description about it?

Thanks in advance.

-- 
Best regards, TRoland
http://www.rotursoft.sk
http://exekutor.rotursoft.sk