What terms describe the different forms of LEDs from (basic electronics to fully functional light fixtures) that are available in the market?

Here are the various terminologies for developmental stages of LED in chronological order:

• LED Die - A small block of light emitting semi-conducting material on which functional LED circuitry is fabricated.
• LED Package - This includes an LED die or more than one LED die with an optical element and mechanical, thermal and electrical interface.
• LED Module - This includes and LED package or an LED die, possibly with an optical element connected to a circuit board, and with thermal, mechanical and electrical interface that are intended to be connected to the load side of the driver.

LED Engine - This is an LED module or array of packages with the associated control gear / LED driver. It is the nearest equivalent to the lamp in a conventional luminaire
 
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