If you need these files, or to sync your computer and the cloud again, you’ll need to redownload the online-only folders. In other words, they only live in the cloud.
If you don’t have enough room on your hard drive to store everything, you can set certain folders to be online-only. This will allow you to access your files from any device.
If you have these apps installed on multiple computers, the changes propagate across them all. When you change something on your laptop, it changes in the cloud, and vice versa. It can be a little confusing at first, but here’s what’s happening: OneDrive, iCloud, Dropbox, and Google Drive are built to keep two identical folders-one in your computer and one in the cloud-in sync by default. All the popular cloud storage services now let you free up local storage on your computer while keeping your files safely stored online-and this is how to make use of them. Disk space is always at a premium-especially as we amass more and more photos each year-so take every opportunity to free up as much as you can.