You hard drive can crash or die completely at any time. Never keep only one copy of any of your files.
Even if you have a warranty, a warranty will not get your files back.
How to Make Backups
External hard drives are ideal for backup. Most external hard drives come with pre-installed, free backup software to make automatic backups. If you do not have or do not want to use external hard drive backup software, use Windows' or Mac's bulit-in automated backup, or use Google to help you find backup software to fit your needs. Additionally, consider making extra backups of old data (such as photos from years past or school work from previous semesters) onto DVDs as well.
Server File Storage
All students and employees have storage space on our servers. Files stored on the servers are backed up automatically, so it is far safer to store your files on the server than storing only one copy on your own hard drive.