Time Machine
Our iMac contains all our photos, music and videos, so losing any of it would not be good. So, when the iMac’s hard drive failed, I was a little anxious to see if Apple’s Time Machine would work as advertised. It did. At the end of re-installing the operating system, I selected to transfer the backup from the Time Capsule, and once that was completed (300Gb over a couple of hours) everything was back to normal - it was like the computer was before it failed.