Closes all open documents. If you have never saved a document, the Save As dialog box is displayed so that you can give the document a name and specify a folder and format to save it to. If you have made changes since the document was last saved, you are asked if you want to save the changes.
In the event you are closing a read-only direct document such as an assembly, you have the opportunity to save changes to indirect or referenced documents that are write-enabled.
When you close a document that was opened from a managed library, you can set options on the Manage tab on the Options dialog box to automatically check in and publish the document.
Save Read-Only Document dialog box