Help with Mozilla Firefox browser

I don't use Firefox anymore 'cause I moved over to Google Chrome last year but I remember there was a 'Clear Your Recent History' button under History on the menu bar. If you haven't got the menu bar activated press the right hand button on your mouse up the top and click on it to enable it. I hope that helps.

NOTE: if you ever get rid of your computer or want to make sure no one can recover any data on your computers hard drive, assuming it has a regular hard drive in it, run DBAN (which is free software) on it which you can get here... dban.org/

it's runs from bootable USB device or CD/DVD media and then permanently deletes ALL data that has ever been on your PC's hard drive as after you run that there is basically no chance someone can recover any data on your hard drive. depending on how large your hard drive is that can take a hours to complete.

WARNING: BE CAREFUL WHEN USING DBAN!!! ; as if you type 'autonuke' when it loads up it will delete ALL data on any hard drives etc connected to your PC when it's ran! ; the autonuke mode is easiest way to use DBAN but you can manually select the drives to wipe.

with that said... you should be able to do a basic clearing of your browsers data by clearing Cache and clearing the previously visited websites in your browsers options. i am using Pale Moon x64 but it should be similar to Firefox.

even outside of DBAN... you could clear your browsers cache etc, like i was saying, and then simply use something like Eraser (i.e. eraser.heidi.ie/ ) to wipe the FREE SPACE on your computer (depending on how large your hard drive is this could take hours).

but even outside of wiping the free space... Eraser is even nice if you need to delete certain files to make sure no one else can recover them. because normally when you delete a file in Windows the normal way (i.e. delete file and then empty the recycle bin) the file is not actually deleted as the OS(Windows etc) simply allows that free space to be written to in the future if needed as the file could still be there. but if you erase a file with Eraser it actually overwrites the entire section of the hard drive where the file your erasing is stored. just to be sure... i adjust things in Eraser's options and switch 'default erasure method' (along with drive erasure method) is 'Pseudorandom Data (1 pass)' as that should be secure enough.

but all-in-all given your situation... just visiting a bank site through your browser i would not really worry about this stuff and just use your computer normally. just be cautious on what programs you run on your computer as the best defense is not getting infected with a virus etc in the first place as if you keep that off of your computer chances are your banking info is not going to get stolen etc. also, just sign out of your banking stuff when done as even if you see your banking links when you type in the browser you ain't got to worry as if you sign out people physically using your computer will have to sign back in should they attempt to visit any of the banking sites you been to.