Backup of disks
Computer program CDs can be very expensive to replace. The cost of the programs can range anywhere from being free to thousands of dollars. If the disk gets damaged or lost, the company that created the CD usually will not replace the disk. To get another disk usually requires the person to purchase the software again.
There is a way to prevent this from happening. You can create an .iso image of the CD. an .iso image is the exact image of the disk but compressed. Various programs make .iso images and burns them back to a CD. There are free ones and paid ones. A couple of programs that does burn .iso images and creates them are Nero and Sonic(there are others. These are just a short list).
You can create the .iso image and store it on your computer, an external hard drive, or a DVD until you need it. If you later find out that you are missing a program CD or the disk is damaged, you can create you another program disk for the for the cost of a blank disk instead of the cost of buying the program over again.
Making a copy of a program CD is legal because you are doing it for backup purposes only. It is not to resell or loan out. Therefore you can make a copy of it.