Diode
A few different parts that are individual diodes, or multiple diodes in a single package. Both regular diodes, and LEDs.
A diode acts like a check valve; it allows current to flow in one direction and resists current flow in the other direction. Consequently, diodes have polarity. LEDs (light-emitting diodes) are just one of many types of diodes. The basis for a diode is a PN junction, which is also an important concept for transistors. To learn about PN junctions and diodes, check out https://www.youtube.com/watch?v=ar7xDMR4P_U
An electronic schematic shows diodes using a symbol that does not look much like the actual part. Too many other parts have the same basic look. The symbols are more unique.
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