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[tigger]

Thanks for your answer.
How could you manage to put that Picture in the Forum?

Lets say there is the

HOME
with subdirectory A
A has the súbdirectory B
B has the subdirectory C

Whenever I have assigned Variables (x, y, Z) in Home I have These variables in A, in B and in C, too.
I can neither assigne those varialbes (x, y, z) in A nor B nor C.

x, y, z are called global variables?

I can not find something in the user Manual to read about it. Could you give some keywords to search it or links which lead me to the pages in user Manual.