This article is from the the Brief Linux FAQ (BLFAQ) Maintained by Neil Zanella firstname.lastname@example.org
First connect to the remote machine using dip or whatever you use. If the remote machine is called grasshopper.uvw.edu and your machine is called kiwi.fruit.org then first type
from your own machine's shell prompt while running X. If you telnet to the remote machine and you're using a modem to connect then your machine name on the Internet may be different from your actual machine name at home so be sure to use the finger command on the remote machine with your remote user name as an argument to find out what your machine name is on the Internet. Assuming your machine name has not changed you must type
on the remote machine if it uses the Korn shell or the equivalent if it uses another shell. You should be now ready to fire up the remote application from your machine.