No Panels at All
The Gnome X11 environment comes with a system called Panel.
Gnome panels are bars where the system include menus, icons, the date, statistics, etc.
Without the bar, it is a tad bit complicated to run programs and do all sorts of things (like switching between windows.)
If the panel software itself did not start properly or crashed, you may restart it with the following command:
In case, however, the problem was that I wanted to hid the two panels I use (the default top and bottom panels.)
So I right clicked and selected the option properties.