Computer programs and apps can always be reinstalled if lost, but data can't be reinstated if I don't have copies. So what do I do?
1. External hard drive
I have two and they contain everything I value. One is permanently attached to my desktop computer and the other moves around, depending where I want it. Two external drives are better than one (it's that mild paranoia!).
These are small, light and easy to carry around. I have several.
I often email important documents to myself, which means they are stored in yet another place. After I spend hours editing or writing, the last thing I need is to lose all that work.
4. The "cloud"
I sometimes (but not always) save files this way. I think that what some people often forget is that the "cloud" is simply someone else's computer, usually belonging to a large company. No one values my files as much as I do, so I would never consider making my sole backup on someone else's computer. It is always possible that there could be hardware failures at their end or that staff could access my files. Told you I am paranoid! 😀
Really, though, we each need to decide how valuable our files and photos are to us and then back them up accordingly. What type of backup do you do?