Organizations have two primary options to host their email servers: on-prem or cloud.
The more traditional option is on-premises, where emails are sent, received, and archived on physical servers in an on-premises location. These servers are usually owned and managed by the domain owner.
With cloud email, you don’t own or maintain the servers. You essentially lease the server space from a third-party cloud email provider. It’s appealing to organizations because it’s generally cheaper to use, scalable, easier to maintain, and provides flexible accessibility. Organizations have multiple cloud-based options when selecting an email hosting service.
Small and medium-sized companies often rely on cloud email from providers like Google and Microsoft. These mailboxes are hosted on external servers belonging to the providers–Google and Microsoft, in this case. All incoming and outgoing emails pass through the provider’s servers.
Larger companies or organizations with considerable security concerns often prefer an internal server rather than an external server maintained by an outside service. This internal server may be on-premises hardware or cloud-based.