You may want to clear the BASH history because you don’t want others to get your sensitive data

1.- To clear history of BASH commands type the following and press enter

$ history -cw

2.- Here  c is to clear history and w to write current history

3.- To remove a certain line only for example say 420 type the following and press enter

$ history -dw 420

4.- To clear current session history

$ history -r

5.- To run commands without saving its trace

$ <space>command

put a space before your command and it wont be saved

6.- To stop saving history for current sassion

$ unset HISTFILE