Light Emitting Diode
From DT Online
Light Emitting Diodes (LED) come in different colours, shapes, sizes and brightness. The more common colours being red, green and yellow.
They are also available in bi and tri-colour versions. Round ones come in 3, 5 and 8mm sizes.
There are also rectangular, square and bar types.
Flashing types are available and seven segment displays are made of a number of LEDs in a particular pattern.