ITBST 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 "Internal table for transfer of text elements to funct.module" 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_ITBST TYPE ITBST.
The ITBST table consists of various fields, each holding specific information or linking keys about Internal table for transfer of text elements to funct.module data available in SAP. These include ELEMENT (Element), BEWZL (Is the text element assigned to the flow table ?)... 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. .