Obviously, if you don't have a "burner" drive, then you can't burn a CD. (You'll need to purchase and install a burner drive.) But if your CD drive is a "burner" and you have a CD burning program on the computer, such as Roxio, Nero, or even the free CDBrunerXP program at the link below, the original disc is placed in the drive, the program rips the data from the CD and it's copied to the hard drive temporarily.. When you place a blank disc in the burner, the program copies the data from the hard drive to the blank disc.. Like magic, a copy of the original.
Hope this helps.