SAP R3 Security Important Tables

USR* table contains user master information.
AGR* tables contains data about roles.
USH* table has change documents information.

USR02	Logon data
USR04	User master authorization (one row per user)
UST04	User profiles (multiple rows per user)
USR10	Authorisation profiles (i.e. &_SAP_ALL)
UST10C	Composit profiles (i.e. profile has sub profile)
USR11	Text for authorisation profiles
USR12	Authorisation values
USR13	Short text for authorisation
USR40	Tabl for illegal passwords
USGRP	User groups
USGRPT	Text table for USGRP
USH02	Change history for logon data
USR01	User Master (runtime data)
USER_ADDR	Address Data for users
AGR_1016	Name of the activity group profile
AGR_1016B	Name of the activity group profile
AGR_1250	Authorization data for the activity group
AGR_1251	Authorization data for the activity group
AGR_1252	Organizational elements for authorizations
AGR_AGRS	Roles in Composite Roles
AGR_DEFINE	Role definition
AGR_HIER2	Menu structure information – Customer vers
AGR_HIERT	Role menu texts
AGR_OBJ	Assignment of Menu Nodes to Role
AGR_PROF	Profile name for role
AGR_TCDTXT	Assignment of roles to Tcodes
AGR_TEXTS	File Structure for Hierarchical Menu – Cus
AGR_TIME	Time Stamp for Role: Including profile
AGR_USERS	Assignment of roles to users
USOBT	Relation transaction to authorization object (SAP)
USOBT_C	Relation Transaction to Auth. Object (Customer)
USOBX	Check table for table USOBT
USOBXFLAGS	Temporary table for storing USOBX/T* chang
USOBX_C	Check Table for Table USOBT_C