Sometimes ago one of my friends, copied some pictures in my USB, then He made them hidden by a software. After that He did a trick (which I did not understand).
After that He told me those hidden pictures won't format if you format your USB. then He formatted the USB, and then He easily made pictures shown.
I mean formatting did not affect those hidden pictures. Now I was formatting that device, it only can be formatted on fast mode, but in full mode it will stop at the end progress and I should cancel formatting.
But Also those pictures (which is hidden) won't be deleted or formatted.
I want to know How such trick can be done? How can I make some data hidden and those data won't be deleted after formatting...