How is an ammeter and voltmeter included in the DC circuit?

Electric circuits are alternating and direct current. In order to measure voltage and current in a DC circuit, a voltmeter and an ammeter are needed (it is in these units that the voltage and current are measured, respectively). The voltmeter to the measured section of the circuit is connected in parallel, while its terminals are connected and measure the potential difference in this section of the electrical circuit. (It is very important that the internal resistance of the voltmeter is much greater than the resistance of the measured area). To determine the current strength of the circuit, the ammeter is connected in series to the break of the electrical circuit (so that the current of the entire circuit passes through it). It is important here that the internal resistance of the ammeter is much less than the resistance of the entire electrical circuit.