History command can be useful for you to refer to, you can type history in your terminal and you will see the commands you had executed.
root@bt:~# history 956 history 957 which .bash_history 958 locate .bash_history 959 nano .bash_history 960 clear 961 history root@bt:~#
Suppose you want to execute history number 960:
You do !960.
Clear history:
root@bt:~# history -c root@bt:~# rm .bash_history
You may have cleared your history with history -c command, but in .bash_history still contains your history up to your first command, you can choose to remove this file if you want.
The implication for history command is that you allow footprinting by a hacker to understand your linux ability through studying the commands you have executed, history command will also review some files or directories you have referred to, and also some configuration you had attempted to execute before.