A Continuous or Permanent power supply (also called Hardwire kit) is a special power supply for permanently powering your dashcam. A Continuous power supply is used as an alternative to the standard cigarette power supply to be able to use the dashcam in parking mode when the car is parked. This is because most cars do not provide power through the cigarette power supply when the car's ignition is off.
A Continuous power supply has a built-in protection device that keeps the car battery from draining completely when the dashcam is used in parking mode. It interrupts the current when the voltage drops below a certain (sometimes adjustable) point, so you don't have to worry about running out of battery power. Connecting a Continuous power supply is preferably done at the car's fuse box.