eMachines computers are usually supplied with one or more hard drive data recovery CDs (also known as eMachines Windows recovery CDs, eMachines hard drive restore CDs or hard drive data restore CDs). The eMachines hard drive data recovery CDs are specifically designed for your eMachines computer, usually contain an image of what was on the computers hard drive when it was first bought, & they allow you to return the machine to its original state (as new). This is particularly useful if the machine has been attacked by a virus, if the original hard drive has developed a fault, or if you simply wish to replace or upgrade the hard drive, & need to re-install your original software.
The eMachines Windows recovery CDs are also sometimes referred to as eMachines Windows installation CDs because they completely erase the contents of your hard drive & then re-install your operating system (Windows ME or Windows XP). However, they differ from normal Windows installation disks in that they usually restore all programs which were originally installed on the hard drive when the computer was first purchased (any additional programs or files which were not originally installed will be overwritten).