Office 365 Focused Inbox - What is it?

I was working on an Office 365 migration project recently and discussed Outlook features with the client, particularly the Focused Inbox feature.  I like to provide more information and references to clients after these types of conversations but found the Focused Inbox’s to be a little scattered online.  Below is a consolidated overview of Focused Inbox and a few extra details.
 
What is Focused Inbox?
The best explanation of Focused Inbox in my opinion comes from the mobile app FAQ.  Here is the explanation from the most recent Outlook mobile app for Android:



What happened to Clutter?
Simply put: Focused Inbox has replaced Clutter but basically with the same functionality.  Clutter moved mail to another mail folder while Focused Inbox keeps your mail in your Inbox but just in a separate Other view.  Microsoft does provide a brief explanation under the ‘What does Focused Inbox mean for Clutter?’ section here.  Other should learn and become smarter the more it analyzes your mail like Clutter did.  Your previous clutter should still be visible in a separate Clutter mail folder in your mailbox.
 
Can mail be moved between Focused Inbox and Other?
Yes, as mentioned in the ‘What is Focused Inbox’ summary.  There are options to move mail between Focused Inbox and Other through the Outlook desktop app, web portal, and mobile app (that is if you choose to keep Focused Inbox enabled).  In the Other view, simply right click and choose ‘Move to Focused Inbox’ or ‘Always move to Other Inbox’ or vice versa if you want to move mail to Other.  On the mobile app, or at least Outlook for Android, tab and hold the message you would like to move.  In message options, choose either ‘Move to Other’ or ‘Move to Inbox’ to move the email to the appropriate folder.
 
Do I have to use Focused Inbox?
No. There are mixed reviews on Focused Inbox online with many users disliking the 'new Clutter' and turning it off.  This can be done in the desktop app, web portal, and mobile app. 
 
Focused Inbox Information Online
Here are a few links from Microsoft that I’ve found useful and used for verification:

• Linked previously: https://support.microsoft.com/en-us/help/4025253/description-of-the-focused-inbox-feature-in-office-365-dedicated
• Instructions for enabling and disabling: https://support.office.com/en-us/article/Focused-Inbox-for-Outlook-f445ad7f-02f4-4294-a82e-71d8964e3978

I’ll look to provide some simplified documentation on enabling and disabling Focused Inbox in the Outlook desktop app and web portal soon.