Resistors are fundamental electronic components that limit the flow of electric current in a circuit. They are used to control voltage and current levels, divide voltages, and provide biasing in various applications. Resistors come in different types, including fixed, variable (potentiometers), and specialty resistors, each designed for specific purposes. They are characterized by their resistance value, which is measured in ohms, and their power rating, indicating how much power they can dissipate without damage. Resistors are widely utilized in virtually all electronic devices, from simple circuits to complex systems, ensuring proper operation and signal integrity.