System Template 
A schema used to create systems that become part of the portal system landscape.
Structure
A system template is a set of defined properties, with or without default values. A template can be manually created by content developers, or automatically based on an application connector.
A template need not contain a full set of property values to create a system. Many values can be added only during the editing phase.
When the system is accessed through a connector, the connector ID is one of the defined properties.
Integration
When you install a portal, you also install predefined system templates for all the connectors that the portal provides. These templates are contained in the System Landscape Templates folder, under 
System Administration
System Configuration Portal Content Templates 
, and can be edited in the Property Editor. Editing a template affects any systems that you create based on this template. See Content
Object Model for information about delta links and inheritance.