Password for Safari

Hi there!
I usually leave my computer idle while it renders the videos that i edit or other reasons and i always seem to find that someone has used my computer to go to the internet. I was wondering if there is any way to put a password on the Safari app. as soon as you click on it, so not just anyone can access it.

Not that I know of, but you can lock your screen so if anyone tries to use it they have to put your password in

*Moved thread to proper forum - Not just anything goes in Anything Goes*