A computer image is a snapshot of your hard drive stored onto another physical device. A computer image allows you to recover from almost any disaster that can effect your computer except for the complete loss of the computer itself. This is because you can not store one computer image onto another computer unless all the hardware is exactly the same.
Many people only backup their data files. While backing up data is extremely important and needs to be done on a regular basis, you also need to protect yourself from disasters that can impact your Operating System and all your Progam Files. A computer image takes care of this.
Without a computer image if you were to lose your hard drive even though your data is backup up you will still need to format your disk, reload Windows Operating System, re-install all your drivers and software, and then customize the computer back to the way it was. This could take many hours of your valuable time or could cost hundreds of dollars if you had to have someone do it for you. By having a computer image, none of this would be necessary. You would simply restore your image and then load your data files if you keep data on your C: drive.
There are many other things that can happen that may force you to have to reload everything. A virus or worm can make your computer unusable. But even things you initiate can sometimes cause you to not be able to boot your computer again. Many times new software intoduced into the computer can casue conflicts and crash your system. Sometimes you can use the System Restore function in Windows but there are times when your Restore Points are corrupt.
Pro-ActiveComputing can create an image of your C: drive for you that you can store in case you ever have the need to do a restore.