BUS000MSG 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 "CBP: Structure for message handler" 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_BUS000MSG TYPE BUS000MSG.
The BUS000MSG table consists of various fields, each holding specific information or linking keys about CBP: Structure for message handler data available in SAP. These include MSGTY (Message Type), TEXT (CBP: Message text), ARBGB (Message Class), TXTNR (Message Number)... 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. .