In case you've ever wanted to get rid of the command history in your terminal (pressing the Up Arrow Key will scroll through all the commands you've ever used), just delete the .bash_history file located inside your home folder (by using the command rm ~/.bash_history).
If you do that through the Terminal (since the file is invisible), the terminal will replace the file with the commands used in the current window (so if you open a new terminal window, use the command, then close/open a new window, the history will consist just of the command to remove the history file).
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