A resistor is a passive, two-terminal electrical component that limits or regulates the flow of electric current in a circuit and converts electrical energy into heat
| • Nominal Resistance | The target resistance value, often grouped into standardized preferred values (such as the E-series like E12, E24, or E96). |
| • Tolerance | The allowable percentage deviation from the nominal value (e.g., ± 5% for standard carbon or ± 0.1% or lower for precision metal/wirewound). |
| • Power Rating | Measured in watts (W) (e.g., \(\frac{1}{4}\text{W}\), \(\frac{1}{2}\text{W}\), 1W). It is best practice to operate a resistor well below its maximum rating (typically around 60% capacity) to prevent overheating. |
| • Temperature Coefficient (TCR) | How much the resistance shifts with temperature changes, measured in ppm/°C (parts per million per degree Celsius). |
| • Working/Maximum Voltage | The highest continuous voltage that can be safely applied across the component. |
| • Package/Mounting Style | Through-hole (axial leads for breadboards and larger builds). |