When you download and install 'Dropbox Desktop Application' on your computer. It creates a folder on your systems hard disk. The folder is named "Dropbox". Anything you add in the Dropbox folder on your computer will be automatically backup up to Dropbox. It will only sync the files in your Dropbox folder. So you can not have Dropbox sync files outside the Dropbox folder. But, there is a way to sync a folder using Dropbox and still access it from outside your Dropbox folder. If you want to access your files from its current location, then move the file into your Dropbox folder and set up a shortcut (Windows), alias (Mac OS X) or link (Linux) to access it from its former location.
Quick Tip to Keep your Photos Safe
Making backups of your photos & videos is a chore you probably skip, but it really doesn't have to be hard. Here's an effortless way to backup photos - PicBackMan. PicBackMan is the easiest and simplest way to keep your photos safely backed up in one or more online accounts. Simply download PicBackMan (it's free!), register your account, connect to your online store and tell PicBackMan where your photos are - PicBackMan does the rest, automatically. It bulk uploads all photos and keeps looking for new ones and uploads those too. You don't have to ever touch it.