GROUP : Group the Related Segments:-

The directive which is used to form logical groups of segments with same purpose or type. This isused to inform the assembler to form a logical group of the following segment names. The assembler passes information to the linker/loader to form the code such that the group declared segments or operands must lie within a 64Kbyte memory segment. Thus all such segments and labels may be addressed by using the same segment base.

PROGRAM GROUP CODE, DATA, STACK

The above statement directs the loader/linker to make an EXE file such that DATA, CODE and STACK segment ought to be lie within a 64kbyte memory segment that named as PROGRAM. For the ASSUME statement, one can utilize the label PROGRAM except than DATA, CODE and STACK as shown.

ASSUME CS: PROGRAM, DS: PROGRAM, SS: PROGRAM.