Server Accounts - These are mail accounts which have a calendar server. Any change made to them is synchronized while online. Note that, users with a server account added before OfficeSuite version 3.0 may need to connect their calendar manually.
Local Accounts - These are calendars that remain locally on the user's computer. Any invitations received in mail accounts that don't have a calendar server are added to the local account. Creating a meeting in the local calendar sends invitations from the first mail account without a calendar server. Local calendars support a nested structure, meaning you can create a specific calendar inside another larger calendar.