UPDATE: As of 2021, ArcGIS content migration (such as items, groups, and users) from one organization to another is now transitioned from Admin Tools for ArcGIS to a more in-depth backup tool in Backup My Org.
Copy
This tool The Copy tool is an Admin Tools feature that creates a new item as a pointer to the original source, which is useful for multiple users that are all working on the same content. Backup My Org’s backup tool possesses the same copy functionality but with a more in-depth way to customize copying items, or backups in this case.
Clone
This tool creates brand new items, with its hosted dependencies configured automatically, and no longer pointing to the original data source it was cloned from. This is a very useful tool for moving content into a new organization. The Clone tool is available in Backup My Org.
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