The unit of electrical resistance is the ohm, symbolized by the Greek letter Ω. Ohm quantifies how strongly a material opposes the flow of electric current. According to Ohm's Law, the resistance (R) of a conductor is equal to the voltage (V) across it divided by the current (I) flowing through it, expressed as R = V/I. Understanding resistance is crucial for designing electrical circuits and ensuring functional efficiency in various devices and systems. The concept also plays a significant role in fields such as electronics, telecommunications, and physics.