Impedance is the measure of opposition that an electrical circuit presents to the flow of alternating current. It combines both resistance and reactance, representing the overall resistance to the flow of current in a circuit.

Common examples of related units of measurements include resistance, which measures the opposition to the flow of current in a direct current circuit, and reactance, which measures the opposition to the flow of current in an alternating current circuit.

• Impedance is crucial in determining the behavior of electrical circuits
• It helps in designing filters, amplifiers, and other electronic devices
• Impedance matching is essential for maximum power transfer in systems