Office 365 is a subscription-based and cloud-based version of Microsoft's popular productivity suite Microsoft Office, which was first launched in 2001. Excel, Word, PowerPoint, and OneNote are all included in Office 365, as with other programs and services including Publisher, OneDrive, Planner, Exchange, Access, SharePoint, Yammer, Skype, and Microsoft Teams, depending on the plan selected.

When it comes to Office 365 licenses, there are options for personal use, multi-user households, students, enterprises, organizations, and educational institutions, among others.

Office Internet, a mobile-only and online version of Office, allows users to receive free access to feature-limited versions of Office programs.