For more information about adding a user to sudo list, see this link.t file with Linux text editors: vi or nano.That is the most common method for package updates and installs for these operating systems.
The upgrade tools and process are quite reliable, but a hardware failure in the middle of an upgrade could result in a severely damaged system.
The upgrade process itself does not modify anything in the /home directory. parts of the Mozilla suite, and the GNOME and KDE desktop environments) are known to overwrite existing user settings with new defaults when a new version of the application is first started by a user.
This is because we do not allow direct listing/access to this link.
The URL is only meant to be used when using the CLI commands as in the one shown above.
Remember to read the Squeeze release notes One of the most important thing I have read is about back up.