clearing off a USB

Hi,
I recently tried to delete everything on one of my usbs so that someone could borrow it. I thought I had deleted everything but when I plugged it into my windows os desktop computer, there was a hidden .trashes file that had all the deleted files. I deleted that [and later learned that to successfully clear it off from a mac os i would have had to delete my trash bin while the usb was still plugged in]. anyway, i'm wondering if deleting the trash in a windows os really would have deleted everything? it showed that the space was free but i'm just a bit apprehensive as there were some things i wouldn't necessarily want the person to see haha

When deleting files off of a USB drive in Windows, you actually delete the file (unless you specifically send it the Recycle Bin), whereas in OS X you need to empty the Trash before the files are actually gone.

I wonder if there's a way to change this setting. I actually prefer the Windows method in this regard.

Actually, in windows when you delete the file it marks the space as write-able, it doesn't actually delete the file until it's written over by more data.

This is why organisations such as the Police can use tools such as Undelete to recover deleted data and why I use an application called Eraser to overwrite data rather than typically 'deleting' it.