What is Regenerative Braking?
It increases your range by returning braking energy to the main battery that would otherwise be wasted.
How does it feel?
When regenerative braking is on, the car will slow down as soon as you lift off the accelerator pedal.
What do the settings mean?
On most EVs, you can set the level of regenerative braking which is happening yourself.
In general, the higher the number, the more regenerative braking there is (and therefore the more range you save!)