What is the difference between CALL FUNCTION and CALL FUNCTION…IN BACKGROUND in SAP ABAP programming?

```html

What is the difference between CALL FUNCTION and CALL FUNCTION…IN BACKGROUND in SAP ABAP programming?

In SAP ABAP programming, the focus keyword CALL FUNCTION is used to synchronously call a function module, which means that the calling program waits for the called function module to complete before proceeding further. On the other hand, CALL FUNCTION…IN BACKGROUND is used to asynchronously call a function module in the background, allowing the calling program to continue execution without waiting for the called function module to finish.

When using CALL FUNCTION, the program flow is blocked until the function module finishes its execution, whereas with CALL FUNCTION…IN BACKGROUND, the calling program can continue its execution without being blocked by the called function module.

```