How do I unhide folders/files so I can see them on my computer?

I've made a bunch of files and folders hidden on my computer so they don't clutter up the place. These are files mostly for backup so I don't need to really use them at all. However, now the time has come that I need to access these files. How do I make them visible again? In the past it was just a matter of opening the "app" and right-clicking, or going to dropbox.com and selecting some option to unhide. I can't find that option now...