https://www.dropbox.com/help/16/enPlease note: New Dropbox accounts created after October 4, 2012 no longer have a Public folder. Don't worry! Every account created prior to this date will still have a Public folder. If you would like to enable a Public folder on a new account, see the instructions below (Creating a Public folder).
However, all the extra functionality provided by the Public folder is now accessible anywhere in your Dropbox. Now all you need to do to share and preview files and folders in your Dropbox is select Share link via your computers, phones, and tablets. Take a look at Dropbox links here or go to this article to see how it works.
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Creating a Public folder
Dropbox links give you everything you need to share and preview files and folders. However, if you’re just a diehard fan of Public Folders, click here to enable one on your account.