You can save as much as you want, but saving in multiple places is probably the best thing you can do. I’m an English person, and as such, I know that I have to write a bunch of papers or do multiple projects that need saving. One of the most stressful things is going through a computer meltdown and having to tell your professor, boss, or authority figure that you just don’t have the document because of a crash. Outlets such as Google Drive, CDs, email, and (maybe if you’re feeling retro) floppy disks can save you from so much hassle. You don’t have to worry about a computer crash because you saved it somewhere else. It can save you the effort of putting more work into a a piece that you already have.
Things so happen though, and sometimes having to start over is a must. Here’s a helpful tip, before you do the dreaded deed again, double check that your Word program did an emergency save. If you sent a draft copy to a professor for looking over, see if you still have that email attachment. Some is better than none, but it could also give you an opportunity to have a fresh outlook on the topic and bring in new ideas without having to go back and make changes. It’s tedious, but it can be a fun process as well. I guess it depends on the topic.