In a lucid dream you realise you are dreaming. That makes it different.
No limits
In reality there are limits. In a dream there are not. Scientific research confirms that your brain is more active during a lucid dream. You are in a state between sleeping and waking.
Can you learn it?
Lucid dreaming can be learned. It begins during the day: look consciously at your surroundings and realise you are awake. In your dream you then notice more quickly what does not add up.
Degrees
There are degrees: from realising you are dreaming, to actively steering your dream. That highest phase asks for practice.
As therapy
Lucid dreaming is also used as therapy, for nightmares, trauma, stress or writer's block.