A family of Microsoft word processing software products for creating web, email, and print documents.
Contrary to what Abject Ignorance scraped up, Content Controls have not yet been provided in the Mac Office UI. They have to be created programmatically. Please see this article by John Korchok:
NOTE that keyboard shortcuts can be assigned to Content Controls which allows for them to be inserted but the features for defining & modifying them are not available. Also, documents which have Content Controls are fully operational but the controls cannot be modified in the Mac Office programs.