Here is the video version, if you prefer it:
If you ever want to shut your system down via the command line, here is how it is done: (Ward, 2014)
shutdown -h now
If you want to restart your machine, execute this:
shutdown -r now
In order to delay the shutdown or the restart, write this (this is the shutdown case):
shutdown -h +numberofMinutes
I usually shut down my computer via the GUI, but there may be some situations where you might have to shut down the computer via the command line (such as when accessing a computer remotely, for example).
Hope you learned something new!
References
Ward, B. (2014). How Linux Works: What Every Superuser Should Know (2nd ed.). No Starch Press. Pages 144-145