I am updating my Tor on Ubuntu and it states:
Do not use the packages in Ubuntu's universe. You'll need to set up our package repository before you can fetch Tor.
It then states that I have to add this line to your /etc/apt/sources.list
file:
deb http://deb.torproject.org/torproject.org <precise> main
I am uncertain how to add a line to /etc/apt/sources.list
.