VSBMAT 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 "Table for Materials / Customer Materials" 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_VSBMAT TYPE VSBMAT.
The VSBMAT table consists of various fields, each holding specific information or linking keys about Table for Materials / Customer Materials data available in SAP. These include KDMAT (Material belonging to the customer), VBELN (Delivery), VBTYP (SD document category), KUNAG (Sold-to party)... 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. .