There are many applications that share the same source package, so I will show three different ways to print the name of the source package.
Knowledge of how to determine when the last time package index files were updated can be very useful when you least expect it. It is not something used everyday, but can be used to monitor or verify when
apt-get update command was executed.
It is very easy to upgrade the whole Debian system, but you can also upgrade only selected packages and skip the rest.
I am constantly moving between fixed list of several directories on daily basis. Using
cd can be tedious at times, so I defined shell function to quickly jump between defined set of directories.