RERF_RAN is a standard SAP Structure so does not store data like a database table does. It can be used to define the fields of other actual tables or to process "Range structure for Entered By selection" Information within sap ABAP programs. This is done by declaring abap internal tables, work areas or database tables based on this Structure. These can then be used to store and process the required data appropriately. i.e. DATA: wa_RERF_RAN TYPE RERF_RAN.
The RERF_RAN table consists of various fields, each holding specific information or linking keys about Range structure for Entered By selection data available in SAP. These include OPTION (OPTION field in structure of SELECT-OPTIONS tables), LOW (Entered by), HIGH (Entered by)... See below for full list along with technical details, documentation, text table, check tables, foreign key relationships, conversion routines, relevant tcodes and example ABAP select code etc. .