Editing Microsoft Exchange Server (section)

==Hosted Exchange as a service==
{{main|Hosted Exchange}}

The complexities of managing Exchange Server—namely running both one or more  Exchange Servers, plus Active Directory synchronization servers—make it attractive for organisations to purchase it as a hosted service.

===Third-party providers===
This has been possible from a number of providers<ref name=hepd/> for more than 10 years, but as of June 2018 is that many providers have been marketing the service as "cloud computing" or "Software-as-a-Service". Exchange hosting allows for Microsoft Exchange Server to be running in the Internet, also referred to as the Cloud, and managed by a "Hosted Exchange Server provider" instead of building and deploying the system in-house.

===Exchange Online===
Exchange Online is Exchange Server delivered as a cloud service hosted by Microsoft itself. It is built on the same technologies as [[on-premises software|on-premises]] Exchange Server, and offers essentially the same services as third-party providers which host Exchange Server instances.<ref name=office365/>

Customers can also choose to combine both on-premises and online options in a hybrid deployment.<ref>{{cite book|title= Microsoft Office 365 Administration Inside Out|last= Puca|first= Anthony|publisher= Microsoft Press|year= 2013|isbn= 978-0735678231|pages= 459–462}}</ref> Hybrid implementations are popular for organizations that are unsure of the need or urgency to do a full transition to Exchange Online, and also allows for staggered [[email migration]].

Hybrid tools can cover the main stack of Microsoft Exchange, [[Skype for Business|Lync]], SharePoint, Windows, and Active Directory servers, in addition to using replica data to report cloud user experience. {{Citation needed|date=January 2016}}

===History===
Exchange Online was first provided as a hosted service in dedicated customer environments in 2005 to select pilot customers.<ref name=hop/> Microsoft launched a multi-tenant version of Exchange Online as part of the Business Productivity Online Standard Suite in November 2008.<ref name=outofbeta/> In June 2011, as part of the commercial release of [[Microsoft Office 365]], Exchange Online was updated with the capabilities of Exchange Server 2010.

Exchange Server 2010 was developed concurrently as a server product and for the Exchange Online service.