SAP AG brought out a client–server version of the software called SAP R/3 (The "R" was for "Real-time data processing" and 3 was for 3-tier): 1) database, 2) application server and 3) client (SAPgui).
SAP R/3 was officially launched on 6 July 1992. Various releases of the software were made through the 90s.
A newer version of the software, with new architecture, was released in 2003-2004, renamed as SAP ERP. ECC is a version name for SAP ERP,(ERP Central Component).
SAP ECC 5.0 ERP is the successor of SAP R/3 4.70. The newest version of the suite is SAP ERP 6.0, Enhancement Pack 7.