Definition - What does Public Folder mean?
A public folder is a construct or function of a software application, typically one that handles data of any kind, that allows a user to share files with other users and devices within the same network or the same computer. A public folder may have different features and setups depending on the application. Some applications that have public folders include Microsoft Outlook, Microsoft Exchange, Dropbox and all versions of Windows starting with Vista.
Techopedia explains Public Folder
A public folder is a quick and easy way to share files and information; the user simply has to move or copy a file into a public folder and it instantly becomes viewable by other users and devices with the proper settings and restrictions set by default by the application. For example, on Windows Vista and higher versions, public folder sharing is turned off by default, so only alternate user accounts in the same computer can have access to the public folder (located at "C:\Users\Public"), but if a homegroup has been set up, all the members of the homegroup have access to this folder automatically by default. The settings can then be changed by the user by going to the Network and Sharing Center section of the Control Panel.
In Dropbox, a public folder creates links to files and other folders that are dragged and dropped into it. Other users can then download, open or edit the files without affecting the original, but if the sharer edits the original files or changes the content of the folders shared within a public folder, then those files or folders also change because of the link.
A public folder usually behaves like any normal folder in the sense that it houses files and can manage them from there, especially in Windows. But the similarity ends there since a public folder is a permanent fixture that cannot be deleted or moved. It provides an easy way to share between users of the same computer and users in the same homegroup without requiring a lot of set up on the part of the user who wants to share. Quick and easy sharing is the ultimate purpose of a public folder in any application that it is implemented in.