What are the units of electrical resistance?

Electrical resistance is the opposition to the flow of current in a circuit. The standard unit for measuring this resistance is the Ohm, named after the German physicist Georg Simon Ohm. Distractors like Siemens and Mhos actually represent conductance, which is the exact opposite (or reciprocal) of resistance. Coulombs is incorrect because it is the standard unit of electric charge, not resistance.