There are only two ways to backup you entire hard drive. You can either image your disk or clone it. What factors should we consider before choosing one of them?
Both cloning and imaging make exact copies of your hard drive's contents. The backup copy includes user files as well as the MBR (Master Boot Record), a table of allocations and all other data (including deleted items). Cloning and imaging are useful whenever we want to restore Windows with settings. Both methods are also essential when we have a complex set of files in the partition.
When you clone a drive, you turn a second drive into a copy of the first, so that we have the two identical drives. This could be an external hard drive connected to the PC via USB cable or enclosure.
With imaging, you create a very large compressed zip file from which you can recreate the drive's contents in the future using a dedicated software for this.
Should your main hard drive crash, a clone will let you easily access your files. In order to do this just swap the drives (on the condition that they represent the same standard, for example, 3.5-inch SATA). Plus, we can always take a portable with us everywhere and we have constant access to our documents.
When it comes to imaging, if your drive crashes, you'd have to buy and install a new internal hard drive. Then you need to launch from your backup program's emergency boot disc, and restore the drive's contents from the compressed file.
The unzipped disk image is basically useless. We cannot connect the HDD to our friend’s computer in order to share movies or music. On the other hand, the image takes up less space than cloning backup.
Thus, personally I vote for imaging. It is more versatile since you can save several images onto one sufficiently large external hard drive, what makes it much easier to store multiple versions of the same disk.
The latest versions of Windows come with embedded tools for backup. However, there are several worth trying specialized programs that can do these chores, such as HDClone. The application is free and can image and clone.