Important References

SAP Technical Tutorials

ABAP
DICTIONARY
INTERNAL TABLES
ALV Reports
SAPSCRIPTS
SMARTFORMS
LSMW
BDC
ALE
IDOC
USER EXITS
TRANSPORTING
ITS

SAP Functional Tutorials

FI (Financial)
CO (Controlling)
HR (Human Resource)
LO (Logistics)
MM (Materials Management)
PP (Production Planning)
QM (Quality Management)
SD (Sales and Distribution)
TR (Treasury and cash)
WM (Warehouse Management)
PS (project Systems)
PM (plant Maintenance)
CA (Cross Application)

SAP BASIS TUTORIALS

SAP References

transaction codes
System Fields
Function Modules
SAP TABLES
code optimization

TOOLS

SQL Trace tool
Runtime Analysis
LSMW
ABAP Query
CTS