- Never keep important data on only one place
- Never store important data on partition where your system is installed
- If you store your important data on some cloud services keep it encrypted
There are several scenarios of loosing your data :
- deletion by accident
- infection by malware
- hardware or software failure
So, if your Windows or other OS is updated regularly, your antivirus is updated regularly, your habits with browsing and installing are safe and cautious you will be safe from malware infection (some ransomware, cryptolocker or similar that can destroy your data...)
Piriform Recuva can save you from accident deletion of files.
For your data (music/photo/documents/movies...) the most safe way is to keep them on external HDD and if not on some cloud service.
Backup-ing data and store them on the same hardware is not logical in some cases. Acronis, Macrium, Paragon, EASEUS... may say different but it is. Why installing some backup solution to keep choking your resources with several processes running in the background when Windows File History is good solution for that stuff also, and it comes preinstalled with Windows (8 and 8.1).
So, if you do a backup, I recommend you to do a "cold backup". To create bootable CD/USB of backup solution that you prefer and choose and do all backuping-restoring outside of Windows. And, of course, store it on some USB flash drive or externall HDD It's lot faster and safer and if some software failure occurs (system brake, wont boot, wrong update...) you can restore your system in minutes (~10-15min.) And use it once a month or often, which way you suit the most.
Hardware failure is just a different story