What is the difference between dimmable LED bulbs and non dimmable?

Other Types of Lights LED Light Bulbs
1

Is it the LEDs, the power supply, or both? If the power supply, what specifically is different?

2

As I known, generally, there little difference on the appearance between dimmable LED bulbs and non dimmable, the great difference is that dimmable bulb requires adjustable light dimmer such as triac dimmer & remote control dimmer & DMX512 controller …(+more)

3

Power Supply/ Driver.

Lots of info here: http://www.designingwithleds.com/category/circuit-designs/dimmable/