A diode is forward-biased when its p-type region is connected to the positive terminal of the supply voltage and its n-type region is connected to the negative terminal. 

The forward current-voltage characteristic displays negligible current for biasing voltages below 0.7 volts, known as the cut-in voltage. However, as the biasing voltage slightly exceeds 0.7 volts, the current in the diode rises sharply.

As a result, fully conducting diodes with different current ratings will exhibit the 0.7-volt drop at different currents.

The diode's current-voltage relationship involves a saturation current that depends on temperature and the cross-sectional area.

The thermal voltage, involving the Boltzmann constant and the magnitude of the electronic charge, is expressed in terms of temperature.

For significant forward current, the diode equation simplifies to an exponential form and is expressed logarithmically in terms of thermal voltage.

Comparing currents for two diode voltages, the equation, using base-10 logarithms, indicates that a ten times change in current corresponds to about a 60-millivolt voltage drop across the diode.