Gates
As we combine two toggle switches to an array to which we can give a 'logical name' we can do the same with transistors. Such arrays are named as "gate". Their construction is deciding under which conditions of the normally two "input" contacts the normally single output will have a low or high potential, which can be conducted to further gates (or e.g. lamps to show a result).
It is the same situation as with the lamp boxes we just have used. Their behavior is strictly dependent on their inner construction and the position of the input switches. Actually important is the possibility of miniaturizing to "Integrated circuits" That can roughly been shown by the production of a printed board in a practical training which may give an outlook to sub-miniaturized mass production by huge enterprises.
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