TrueDisc... If you backup your files to optical disc, you know how fragile those backups really are. Scratches, labels, even age or poor manufacturing can make those discs unreadable within months.
A master copy contains extra information that allows TrueDisc to replace damaged parts of the file. To make a master copy, TrueDisc splits your file up into small parts, called cells. TrueDisc then adds specially-crafted redundant cells. Together, your file's original cells and the redundant cells make up the "master copy."
When you want to copy a file back off disc, TrueDisc reads the master copy. If any of the original cells stored in the master copy cannot be read, TrueDisc replaces them with one of the redundant cells. In this way, TrueDisc can make a perfect copy of your original file, even when the disc becomes damaged.
The specially-crafted redundant cells created by TrueDisc are not mere copies of your data. Instead, like "stem cells" in the human body, they can be transformed into whatever original cells are missing. To get the same level of damage-protection TrueDisc provides by burning copies to multiple discs yourself, you'd need to burn as many as 16 discs for each file you wanted to protect. Even then, you'd have to write special software to recover the data and you still may not be able to recover the entire file, depending on how the discs themselves were damaged.
TrueDisc is smart when it comes to creating redundant cells. TrueDisc will automatically use any available space on the disc, so you always get the maximum possible damage-resistance. When you burn less amounts of data to disc, lots of redundant cells can be added. When you burn a lot of data to disc, less redundant cells will be available for TrueDisc to substitute later if there's file damage. Either way, TrueDisc provides the best damage-protection possible. The TrueDisc format supports burning up to 600MB of data to CD and up to 4.1 GB of data to DVD.
TrueDisc creates CD-Rs and DVD-Rs that are compatible with every major operating sytem. Since TrueDisc stores master copies in the standard CD-ROM and DVD-ROM filesystems, you don't have to use TrueDisc to read the master copies, or even have TrueDisc installed on your computer. TrueDisc's file format is an open specification, so any software can read a master copy and recover your file's original cells. But remember, only TrueDisc can correct disc damage, so you should always use TrueDisc to restore your files whenever damage is suspected.
With TrueDisc, there's no special hardware or media to buy; it works great with the burner and blank discs you already own. And to make it easy for you to share your TrueDiscs with friends and family, a free copy of the damage-correcting TrueDisc reader is automatically included on every disc you burn.