Ohm's law basically states that the current being conducted through two points in a conductor is directly proportional to the potential difference in voltage across the two points, and indirectly proportional to the resistance between them.  When electrical current flows through an electrical wire, for example, there is a natural resistance to the flow of the electricity.  This natural resistance is measured in units called Ohms, in honor of the discoverer of this characteristic.  Electricity normally flows from a high potential point, which is positive, to a low potential point, which is negative.  The resistance of the conductor itself restricts, or impedes the flow of the electrical current at a constant rate.  The formula for calculating electrical current is this:

I = V/R  The "I" is electrical current, measured in amperes, or amps.  The "V" is the potential difference between the two points, measured in volts, and the "R" is the resistance, which is constant, measured in Ohms.