When you start a shell session, it opens in your home directory.
Why home?
It keeps your stuff segregated from other peoples’.
It gives you a separate programming (scripting) space for your own work.
It lets you set your own preferences for everything you use: web browsers, text editors, terminals/shells, etc.
It gives you a place to share your web pages.
Optional:
Take a look from the inside out: Leave the GUI
Edit the file /etc/inittab:
gedit /etc/inittab
Find the line:
id:number:initdefault:
and change the number from 5 to 3.
Save and exit the file.
Log in again
Log out, then log back in again as root:
root
<password>