macOS Sierra: Folders that come with your Mac
Important: Your home folder and certain other folders can’t be renamed. It’s best not to rename or move folders that came with your Mac. Many of these folders have special uses and are necessary for your Mac to function correctly.
This folder contains apps, including Mail, Calendar, Safari, and many others. Apps in this folder also appear in Launchpad. If you try to drag an app out of the Applications folder, it isn’t moved; instead, an alias is created. If you want to uninstall an app, see Install, update, and uninstall apps.
This folder contains fonts, Internet plug-ins, and other items used by apps that are available to all users of your Mac. Don’t use this folder to store files and folders you create. Instead, use the home folder or the iCloud Drive folder (Desktop or Documents).
This folder contains the macOS operating system. You can’t change the name or location of the System folder or the items within it.
This folder contains the home folders of all the people set up as users on your Mac. When you’re logged in, the icon for your home folder looks like a house, and the other home folders look like regular folders. If you log out and someone else logs in, that person’s home folder then looks like a house. The Users folder also contains the Shared folder. Items in the Shared folder are available to anyone who uses your Mac.
Your home folder is named with your user name and has folders for your desktop files, downloads, pictures, documents, movies, music, and any public files. You can create folders in your home folder.
Additionally, you can create folders in your iCloud Drive folder, the Documents folder, or on the desktop (on your Mac or in iCloud Desktop and Documents) to organize your files. There are certain locations where you may not be able to create additional folders. For example, you can’t create folders in the All My Files section of the Finder sidebar.