combine to seperate objects in blender

Hello everybody. :smiley: I wanted to ask, if somebody could help me. I’m about to making a realistic person and I started with the body and the arm. But they both are seperate Mesh-Objekts. How can I combine both objekts, to put them together.
I selectet the Objects, pressed “w” and then “union”, but it didn’t work. I testet the other functions, “intersect” and “differnence.” I tested it several times but without succes.
can somebody help me . . . ,please ? %|

Join Objects in the object menu.