SAP tcodes (transaction codes) are an easy way of executing SAP programs and reports. These programs are written using ABAP code and essentially make up an SAP system interface and functionality. I.e. almost every time you perform a specific action within SAP, such as executing a tcode, clicking on a link, running a report or even creating a report you are executing an SAP program.
As well as the programs that make up the SAP development environment there are thousands of programs/tcodes which have already been created by SAP which perform a multitude of very useful functionality. Also see SAP ABAP reports which are also written using ABAP but offers the user a large amount of reporting functionality.
Popular SAP Transaction Codes
SE80
SAP object navigator
AL11
SAP directory structure
BAPI
BAPI Explorer to view SAP bapis
OLE
OLE Processing
SM30
table maintenance for SAP databases
SM35
Batch input processing
VOK2
Maintain Output Determination
WEDI
IDoc and EDI
Index list of t-codes available in SAP beginning with the following characte
