T100C is a standard SAP Pooled Table which is used to store Message Control by User data in SAP systems, such as SAP R/3, S/4HANA, depending on the version and release level.
The T100C table consists of various fields, each holding specific information or linking keys about Message Control by User data available in SAP. These include ARBGB (Application Area), MSGNR (Message number), UNAME (User Name in User Master Record), MSGTS (Active message type)... 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. .