we are using exchange server 2016 and the major change in Exchange Server 2016 is server role. In Exchange 2013, there were three roles, Mailbox server role, Client Access server role and Edge Transport server role. Exchange 2016 has just two server roles, Mailbox server role, and Edge Transport server role.
Mailbox Server Role: Mailbox server role in Exchange 2016 compared to Exchange 2013 includes both the Mailbox server role and Client Access server role. This simplifies the installation and management of Exchange 2016.
Edge Transport Server Role: Edge Transport server role is similar to Transport role in Exchange 2013. It is installed in a DMZ network and provides anti-virus and anti-spam functionality. Review collected by and hosted on G2.com.