A resistor is a fundamental passive electronic component designed to introduce a precise and measurable resistance into an electrical circuit. This component limits the flow of electric current by dissipating electrical energy, typically in the form of heat, when a potential difference is applied across it. The resistance value, measured in ohms, determines the opposition to current flow and is crucial for various circuit functions, including voltage division, current limiting, and setting operational impedance for other components. Resistors are fabricated from various materials, such as carbon film, metal film, or wire windings, allowing them to operate across a wide range of electrical parameters and power tolerances.