Office Online and Office Online Server

Office Online delivers Microsoft-hosted Web applications that enable viewing and limited editing of Excel, OneNote, PowerPoint, and Word documents in a browser. They lack many features of the Office suite; for example, users cannot work on documents while offline. However, they can be useful for traveling workers or workers who do not have a dedicated installation of the Office desktop applications but need to quickly review and make small changes to documents. Office Online also has collaboration features that are not available in the desktop Office suite, such as coauthoring (group editing) in Excel. These features can be useful for group work on Office documents.

Microsoft continuously makes small improvements to Office Online, which is generally more capable than the corresponding on-premises software (Office Web Apps). For example, improvements rolled out in July 2015 included Word text formatting enhancements (such as autocorrect for capitalization) and a PowerPoint Reading View designed for small screens.