Attributes in the Interface Format 
Use
You use the Attributes function to define the processing parameters for the interface format. These are used by system when the data is exported. They determine how the interface format will be used in the SAP System.
Features
The attributes can be changed during or after the processing of the interface format.
For the process control:
For storing the interface results:
Activities
You use the Attributes function to assign the attributes at any time during the editing of the interface format.

You must assign the attributes to the interface format before you generate the export program.
If you assign the attributes to the interface format later, you must regenerate the export program.