Lil help with data recovery :(
Well i recently got a virus (how i do not know all i know is that my firewall had a low setting when i did and i ended up getting bad results) and ended up having to reformat my hard drive. Now i remember a friend saying that when a hard drive erases data it isn't actually taking it off the drive but simply putting a coat of grayscale or something like that on the hard disk. I have a couple things that were extreamly important to me and i didn't get a chance to back up so if there is any way to do data recovery after the reformat (i don't care what i have to do ill do anything to it) can someone please give me some help. I am pretty sure there is a way as my friend(who unfortunitly i lost contact with) said the only way to destroy whats on your hd is to put a sledge hammer/shot gun to it so if anyone knows i would be greatly indebted to them for their help if it is given. Thanks.