Why is low voltage called ground?

Question

Electronics

Good afternoon, tell me one nuance.
The diagram shows two voltages, high and low
. Low is denoted as GND.
Will both GND - ground and GND - low voltage occur in the MK at the same time?
And how is the operation of capacitors related to TTL in the dynamic mode of operation of the device?

Answer 1

In electronics and electrical engineering, voltages are measured relative to a certain point called "zero". Because usually this point is grounded, it also has the name "ground" or "ground" (GND as in your case).
Voltage is a "potential difference" i.e. measured between two pins. On one output, the voltage cannot physically be either low or high.
In some MKs, for the convenience of wiring the board, several GND pins are provided. Schematically, inside the MK they are interconnected, there is no difference between them.
the operation of capacitors with TTL is not related in any way

Answer 2

For microcircuits powered by one or more sources of the same polarity, minus is often denoted GND (ground). The ground can be different, for example, signal, ground connection, ground.
And in general
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