I am so aware of the potential of lost data that I have multiply copies of just about everything but my operating system. My son comments on my multiple copy thing but I seldom lose data. I had rather waste HD space than to have data disappear. With HD's being so cheap there is no excuse for NOT having
backups of ALL data. A TERAbyte for less than $100 is cheap. I remember paying over $100 for a 20kbyte hard card.