This is necessary thing to do if you have access to many servers, and too many configurations to remember and typed, from the user, hostname and port number. You can make this short with ssh alias.

ssh alias allow you to connect your remote machine just by words.

# ssh mymachineor
# scp file.txt mymachine:~/

Isn’t that awesome? You can configure all your host in a config file, located at
~/.ssh/config
And below are the sample configuration

Host mymachine
HostName [ip address or hostname]
User [username]
Port [port number]

You can just add alias for another host using the same syntax like above, in the same configuration file. If you’re connecting to default port, which is 22, you can just ignore the “Port” configuration line.

If you placed the tricks of ssh’ing into your remote server without password, you can go into with less typing, but be carefull with your private key, as it is the key into your server.

Please refer here, as this is my source
http://www.innovatingtomorrow.net/2008/01/21/type-less-ssh-aliases