That is a description of three different views of the same e-mail account, each using a different e-mail client. I believe Microsoft may be partially to blame for the confusion.

I will never again use an e-mail client that doesn't have an integrated bayesian filter (or equivalent).

Windows 11 has a new Outlook email client, and here's a closer look at the new design.

You choose. Yes, other e-mail clients can integrate multiple accounts, but Outlook’s advantage lies in its native support for Exchange.

Outlook for Windows app replaces Mail and Calendar in new Windows 11 preview Outlook for Windows client is still a preview with some missing features.

Microsoft has today issued an update on when users can expect to see the new Outlook client launch as a replacement for the built-in Mail & Calendar apps on Windows 11.