Erasing Data from HDD

　　I use my PCs in both my office and my home. The data is stored on both PCs' HDD and on the internet so that I can do some deskwork also in my home. It is a very comfortable working circumstance, but one of my those PCs got outdated and I decided to throw it away. The data on its HDD was erased totally by myself, I believed, but the PC experts apparently can revive the data. That was why I took the PC to the Medical Association that I belong to. The association has a data-erasing machine and this machine can make the HDD eternally unusable by strong magnetic energy. I'll show you the picture of the machine. It took about ten minutes to clear the HDD and the private data on the patients was completely erased.