Office 2021 is a one-time purchase that comes with classic apps like Word, Excel, and PowerPoint for PC or Mac, and does not include any of the services that come with a Microsoft 365 subscription.
With a subscription, you get the latest versions of the apps and automatically receive updates when they happen. The apps can be installed on multiple devices, including PCs, Macs, iPads, iPhones, Android tablets, and Android phones. Microsoft 365 also comes with services like 1 TB of OneDrive storage, 60 Skype minutes per month, and Microsoft chat and phone support. Microsoft 365 is a subscription that comes with premium apps like Word, Excel, PowerPoint, OneNote, Outlook, Publisher, and Access (Publisher and Access available on PC only).
