Folders can be shared with any user and your recipient is not required to have a Syncplicity Account. What happens when a user receives a folder depends upon whether or not they currently have a Syncplicity account of their own.

Recipient has a Syncplicity Account
Your share recipients will get an email notification with a link that will take them directly to the folder that has been shared with them online. If they have installed the Syncplicity client on their computer, they will also receive a pop-up notification asking them to whether to sync the folder to their computer and where the folder should be synced to. If the user accepts, the folder will be created on their computer and the files will then immediately download to their computer. If the user declines, the folder will continue to be accessible to them online but will not be synchronized to their computer.

Recipient does not have a Syncplicity Account
Your share recipient will get an email notification which links them directly to the folder via the Online File Browser. Depending upon the permissions granted to them, they can view, upload, download, and edit the files in the shared folder. At any time, the recipient can go to the Account tab and set up a new account for themselves. This will allow the recipient to download a Syncplicity client for their computer and have the files be automatically synchronized.