Finally, Dropbox. Go to the same spot in the taskbar as in the Google Drive example, only click the Dropbox icon this time. (On some PCs, the Dropbox icon may appear next to the upward facing arrow on the taskbar.)
Click the settings cog in the upper right corner of the pop-up window that opens and select Preferences...
Another window will open. There click on the Account tab and choose Selective Sync...
Yet another window opens with a list of folders on your PC. Just de-select the folders that you don't want to keep on your hard drive and click Update, then OK.
In the case of both Dropbox and Google Drive you can always access files not on your hard drive by visiting the website for each service.
What to put in the cloud
Now that you know how to leave your files up in the cloud, the question is what should you leave up there?
If you have a large amount of cloud storage the easiest option is to offload large files that aren't used very often, such as videos or pictures. Those with less storage may have to be more selective, possibly even choosing a mix of documents, photos, and videos.
It's unlikely that your files will disappear from the servers of Dropbox, Google, Microsoft, or any other well known cloud storage provider. Nevertheless, it's still wise to make your own backup of cloud-stored files on an external drive in your own home or, at the very least, with another cloud storage or cloud back-up provider.
Also, keep in mind that once you start depending on the cloud to be your primary storage for personal photos and documents, it pays to maintain the best security you can. Dropbox, Google, and Microsoft all offer two-factor authentication. Make sure you use it. Your password should also be at least 10-12 characters long and completely random. Use a password manager like KeePass or LastPass to store your passwords if you're worried you'll forget it.
Other than that there are also the privacy implications of storing personal data in the cloud. But you've probably already considered that since you're using cloud storage to begin with.
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