What is difference between the isolated of LED driver and non-isolated of LED driver?
The work flow of Isolation of LED driver as follow:
Input power 110Và rectifying à filtering  à switch transistor of ICà High-frequency transformerà  geted output voltage.The contact is isolated between the output side and input side by transformer. so the security.
Non- isolated LED driver is used capacitance + Resistance To reduce the voltage. But it still has high voltage(with input 11V) after reduce the voltage.

used in the low voltage led lamps,the lamps have 110V, who had touched the danger of electric shock.Very likely People is danger of electric shock when touched the led lamps.

Summary:

Non isolation: input and output power of common ground.

Isolation: input and output power with no common ground, a transformer separated.