Aliases are shortcuts for certain commands. For example, if your current directory is /usr/bin and you want to navigate quickly to /var/cache/apt/archives you can do a "cd /var/cache/apt/archives", but this is quite long and you probably want to save time. So this is where aliases come in help. You can do only a "archive" or a "pak" command and the same action is accomplished.
First, edit your ~/.bashrc
and make sure that it contains the following three lines (if not add them editing the file)
if [ -f ~/.bash_aliases ]; then
After this all you have to do is edit your ~/.bash_aliases file and add your own aliases.
alias dld='cd ~/downloads'
alias x11='nano /etc/X11/XF86Config-4′
alias pak='cd /var/cache/apt/archives'
Save and exit the file.
In the above examples, "dld", "x11" and "pak" commands will execute the exact command from the right side of the equal sign.