Office 365 is Microsoft's subscription based cloud solution for business productivity. All server side components are hosted at Microsoft managed datacentres. Customers that subscribe to O365 have access to the latest business productivity software and can choose to be "entirely cloud based" or have a hybrid configuration where some on-premise servers are retained.
Office 365 comprises of several Microsoft products for business productivity that are accessed through a subscription model. The offering currently includes Microsoft Exchange, Microsoft Lync, Microsoft SharePoint and Microsoft Office. Other related products include Microsoft Dynamics CRM Online and Microsoft Project Online.
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