It's vital that you develop the habit of backing up your Mac, however you use it. When you've spent hours, days, months working on your Mac, the last thing you want to do is redo it all because it's been lost. Neither do you want to put your photos at risk, see your music go up in digital smoke or trash the first draft of a book by accident.
Fortunately, none of these unfortunate scenarios need to happen if you take daily care of your data. Implementing a structured, multi-location backup system isn't difficult - there's also plenty of excellent backup software out there to help. And, a few hours spent setting it up can save you days or months in the long run, when you neatly sidestep having to recover – or recreate – your lost work. Quite apart from the practical benefits of a back-up routine, putting one in place now will save you the heartache of losing your digital memories later.