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"Collaborating", by contrast, is how you grant access to people with a Box account (UTBox or external) for not only viewing, but changing or adding content to the folders or files to which you grant them permission. Multiple Collaborator roles allow you to control the privileges you grant to someone for changing and creating new content within a folder, or uploading revisions to a file. To add someone as a Collaborator, they must already have a Box account, either through UTBox or via a an external enterprise or personal Box account.
Sharing will allow a person who has permission to access a file or folder to view and, if their role permits it, download contents of a folder or a specific a file. However, they will not be able to make changes to the contents of the folder, nor will they be able to upload new or revised content unless they are granted "Collaborator" access.
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