provide protection for Ubuntu users so that they would not execute commands such as "rm -rf /" improperly

There should be a feature on Ubuntu so that users will be warned when trying to execute particularly powerful commands such as "sudo rm -rf /". The warning should consist of a question if the user wishes to continue with this command and also a reasonable explanation as to what that particular command does and what could happen if that command is executed.

This feature is particularly useful if that command was given to the user with the intention of destroying his OS or due to a typo by even the most skilled Linux user.