The memory area of each main session has an area called ABAP Memory, which the programs in the internal session can access with EXPORT TO MEMORY and IMPORT FROM MEMORY. Data in the ABAP Memory is conserved through a sequence of program calls. To transfer data to a called program, it can be placed in the ABAP Memory with the EXPORT statement before the program is called. The internal session of the called program then replaces the internal session of the calling program and the data can be read from the ABAP Memory with the IMPORT statement. Data can be passed in exactly the same way when the system returns to the calling program.
The SAP Memory is a memory area to which all sessions of a SAP logon have common access. In ABAP programs, the SET PARAMETER and GET PARAMETER commands can be used to access the so-called SPA/GPA parameters stored in the SAP Memory. Input fields on screens can be linked to this type of parameter and default entries thereby established.