CDLineDataStrucure are used to describe three basic types of elements, which are specified in the Organization field:Standard files,Database Blocks,Work areas or linkage areas.
CELineFieldComplement allows to indicate the controls defined for the field, the branching, the fields which will be updated ,the source of the data displayed etc...
The CompositionCELine allows to identify the position on layout lines, the source of the data, and the conditions under which the data is to be moved into the Data Element (defined or not).