I get this question a lot. After my description of it many people react with “Oh, that is cool. I think I’d use that.” Given that, I thought I would describe it to you here in this short blog.
Dropbox is a service (free or paid) that is similar, but better, than its competitors, including: Microsoft OneDrive, Google Drive, box.com, Amazon Cloud Drive and Apple’s iCloud Drive among many others. Why is it better? I believe that overall it is way more robust than everyone else’s service. However, they all work in a very similar fashion.
Again, Dropbox is a service. That service is to share your files among your devices and with others (as you choose). It works by installing the Dropbox app on your Mac. Get it by clicking this sentence. The app creates a folder in Finder called, cleverly, Dropbox. Anything you put in that folder gets copied to the Dropbox server where you can access it from any Internet-connected computer in the world (with your login/password). You can also access those files on your iPad or iPhone using the Dropbox app from the App Store or on another Mac or PC you own.
Once files or folders are in Dropbox, you can easily share them with others. Right-clicking on a file or folder reveals an easy way to copy a link to that file to email to others. This is great for sharing huge files or many files that would be impractical to share directly via email.
Dropbox gives you 2GB of storage (in the Dropbox folder on your Mac and on their server, of course). This should be enough for many, many documents. It will not work well for photos or videos, but the Mac/iPad/iPhone Photos app is the right tool for that job. The next step beyond the free 2GB Dropbox storage is a huge leap up to 1TB (1000GB) at $10/month or $100/year.
Once installed, Dropbox enables a feature that I suggest you disable - “Enable camera uploads.” This attempts to copy all pictures that enter your Mac onto Dropbox, which will quickly fill it. You can disable it in the Dropbox Preferences.
Give it a try - its free! I have tried so many times to break Dropbox and it is just such a robust piece of software. Amazing and really useful.