If it's the same set-up as a 2005 Hyundai Elantra GT with disk brakes all around (my car), then it's pretty simple. When you pull the e-brake lever, it tightens 2 cables which pull individually on a lever that is attached to each caliper. This lever turns the piston inside the caliper which tightens the pads on the rotor. Thus, your vehicle stays in place (theoretically).
If your cable is too loose or your pads are too worn, then the parking brake will not engage. Or in my case, if both brake cables rusted to hell and then snapped, it won't work either.
in the cabin under the parking brake
Get your brakes checked. It can be something simple, or it can mean impending doom.
quoted $300 for front brake pads, figure I can do no own for less
No. Usually the parking brake is a separate mechanism from the driving brakes, and its usually only found on the rear wheels.
If parking lights stay on after the car is turned off on a 2001 Hyundai Elantra than the brake switch is malfunctioning. The brake switch turns off when pressed in and if it does not work the lights of the vehicle will stay on.
the switch needs to be adjusted
Its because you are low on brake fluid which means you have a leak or that your brakes are worn down and need to be changed soon.
Only on air brake vehicles.
a hairdryer!
Parking brakes apply generally on rear wheels to control enough sliding of the vehicle.
If you want the parking brake to work, yes.
You will wear out the brakes prematurely and you may also overheat the brakes and experience brake fade (no or poor brakes).