All European users of almost any operating system have two problems: The first is to tell the OS that you have a non-american keyboard, and the second is to get the OS to display the special letters.
Under Linux you change the way your computer interprets the
keyboard with the commands xmodmap and loadkeys. loadkeys
will modify the keyboard for plain Linux while 'xmodmap' makes
the modifications necessary when the handshaking between X
and Linux is imperfect.
To display the characters you need to tell your applications that you use the ISO-8859-Latin-1 international set of glyphs. Mostly this is not necessary, but a number of key applications need special attention.
This Mini-Howto is intended to tell Danish users how to do this, but will hopefully be of help to many other people.
If you continue to have troubles after reading this you should
try the German HOWTO, the Keystroke HOWTO for Linux or the
ISO 8859-1 FAQ. They have
tips for many applications. Many of the hints contained herein
are cribbed from there. The HOWTOs are available from all
respectable mirrors of sunsite.unc.edu while the ISO 8859-1
FAQ is available from ftp.vlsivie.tuwien.ac.at in
/pub/8bit/FAQ-ISO-8859-1.