How do you identify diodes?

Identify diodes by their numbering system, which follows the format 1NYYY. The number 1 indicates a diode, N indicates that it is a semiconductor, and YYY is a serialized identification number. Sometimes a letter suffix follows the number, such as M for matching devices or R for reverse polarity.

Some diode manufacturers use color stripes to indicate the diode's identification number. Black, brown, red, orange and yellow stand for 0, 1, 2, 3 and 4, respectively. Green, blue, violet, gray and white stand for 5, 6, 7, 8 and 9, respectively. For example, a red-yellow-blue diode is a type 246 semiconductor diode, or more accurately, a 1N246 diode. The colored end also serves to indicate the diode's cathode, or positive, end.

A diode is a two-terminal electrical component that permits the conduction of an electric current in one direction while blocking the flow of current from the opposite direction. Most modern diodes are made of silicon.