This is the ultimate way of protecting data stored on a computer and it involves encrypting the whole hard drive. Full disk encryption happens at a hardware level and all the contents of the hard drive are inaccessible to all but the one with a key to decrypt it. Therefore, a user of a computer that has full disk encryption normally has to provide the secret key for decryption before the computer can boot into an OS. When a hard disk is encrypted, all the data inside it is stored in a form that is unreadable. The data is only restored to a readable form if the correct key is provided. The advantage of this is that it is a simple security solution that has no pressing demands on the end user. The full disk encryption program will keep data encrypted unless it is being read or modified. Newly written data will also be automatically encrypted. The main disadvantage of this encryption method is that it tends to slow down the access times to data due to the encryption and decryption processes that have to take place in the background. Nevertheless, it is ideal for a workplace environment with portable computing devices.