Explanation of the source system tree:

The source systems are under the root:
@6K@ SAP source system.
@6L@ BAPI source system.
@6M@ External system (PC file on the workstation or file on theapplication server).

The application components are under the source systems.
@6F@ Application component.

The InfoSources and InfoObjects are arranged under an applicationcomponent. Data can be loaded for these from the source systems inquestion.
@6E@ InfoSource for transaction data.
Only InfoSources with an active communication structure and activetransfer rules appear in this tree.
@81@ Active characteristic (InfoObject) for which master data,
texts and hierarchies can be collected.