Outlook on the web, on the other hand, is the webmail version of Outlook, allowing you to access your email account through your web browser. It’s the most recent iteration, originating from a long line of apps included in Microsoft Office suites and standalone programs, so you might say it’s the longest known, as it brings to the table all the features and improvements implemented over the years.

To be precise, Outlook for Microsoft 365 is the version of the app installed on desktop or laptop computers. The name stuck nonetheless and nowadays can be found all over the Internet, including tech community forums and specialist websites. This can be very confusing, especially since the name doesn’t explain whether the user means the app installed locally or the webmail version.

Both come as a part of the Microsoft 365 subscription, which is probably the reason why so many users came to name them “Outlook 365”. There are two Outlook versions which this name may relate to: Outlook for Microsoft 365 and Outlook on the web.

It might come as a bit of a surprise, but officially, there’s no such thing as “Outlook 365”. If you have commissioned a HTML custom email signature from us, or created your own, here is how to install it in Microsoft Outlook:

Add email signature to outlook online