The ssh is an encrypted client for login to remote machines. It overcomes the security issues surrounding telnet. The password as well as data is transmitted encrypted. Note that secure shell software can also be obtained for MS Windows (from http://www.ssh.com).
You can login to another machine with the ssh command.
The command ssh starts a new shell on the remote machine and
also executes the start up files .bash_profile (and .bashrc). If you are remotely logged on to a machine, you can temporarily
return to the session on the original machine by typing 
Ctrl-z
as the first characters on a line. To return the session on the remote
machine, type fg.
You can also use secure shell to copy files to/from remote machines. The command to use is scp. For example, the following command copies the directory program4 (for login id jhack) recursively from the server onyx.boisestate.edu to your home computer (if you execute this on your home computer).
scp -r jhack@onyx.boisestate.edu:cs125/program4 .
If you would like to be able to access your home computer from school, you need to either have DSL or cable access. Then you need to run the secure shell server on your home computer. Under Linux the secure shell server comes with the standard distribution. Then you can use ssh/scp to your home computer from anywhere on the Internet!