Abap Objects and table type

Hi,

The following is a public attribute in the class CL_MEREP_SYNCBO_META

data FIELD_GROUPS type MEREP_TSYNCBO_FIELD_GROUP read-only .

MEREP_TSYNCBO_FIELD_GROUP is a table type having ref type CL_MEREP_SYNCBO_FIELD_GROUP (which is a class)

What is the meaning of such table type?

Regards,

Ravi