Office Web Apps is a web-based version of the Microsoft Office productivity suite. It includes the web-based versions of Microsoft Word, Microsoft Excel, Microsoft PowerPoint, and Microsoft OneNote. The web applications allow users to access their documents directly from anywhere within a web browser as well as share files and collaborate with other users online.

Office Web Apps Server is a new Office server product that delivers browser-based versions of Word, PowerPoint, Excel, and OneNote. A single Office Web Apps Server farm can support users who access Office files through SharePoint 2013, Lync Server 2013, shared folders, and websites. The new stand-alone deployment model means that you can manage updates to your Office Web Apps Server farm independently of other Office Server products that are deployed in your organization.

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