Office 365 is Microsoft Cloud Base SAS (Software As a Service) model.
Ref: https://products.office.com/en-us/business/microsoft-office-365-frequently-asked-questions
Office 365. "Office
365" refers to subscription plans that include
access to Office applications plus other
productivity services that are enabled over
the Internet (cloud services). Office 365
includes plans for use at home and for business.
Learn about Office 365 for use at home. Office 365 plans for business
include services such as
Skype for Business web conferencing and
Exchange Online hosted email for business,
and additional online storage with
OneDrive for Business.
Many
Office 365 plans also include the desktop version
of the latest Office applications, which
users can install across multiple computers
and devices. The fully installed applications
include: Word, Excel, PowerPoint, OneNote,
Outlook, Publisher, and Access. (Publisher
and Access are available on PC only.) And
you can install them across multiple devices,
including PCs, Macs, Android tablets, Android
phones, iPad, and iPhone. When you have an
active Office 365 subscription that includes
the desktop version of Office, you always
have the most up-to-date version of the applications.
The Office 365 plans that are online-only are a great
choice for certain business needs, and they
are designed to work with the latest version
of Office, Office 2013, and Office 2011 for
Mac. Previous versions of Office, such as
Office 2010 and Office 2007, may work with
Office 365 with reduced functionality.
Get more details about which Office versions are supported. NOTE: This compatibility with
Office does not include the Exchange Online
Kiosk or Office 365 Enterprise K1 plans.
All Office 365 plans are paid for on a subscription
basis, monthly or annually.
Microsoft Office.
"Microsoft Office” is the name we still use
for our familiar productivity software. Office
suites are available as a one-time purchase
and include applications such as Word, Excel,
and PowerPoint, which can be installed on
only one PC or Mac. The applications are
not automatically updated; to get the latest
version, you can purchase the product again
when the new version becomes available. The
latest versions currently available for one-time
purchase are Office 2016 for Windows and
Office 2016 for Mac. These suites do not
come with any of the cloud-based services
included in Office 365.