Backup cameras do not need a lot of explaining.  When the vehicle is put into reverse there is an image of what is behind you.

Most vehicles now have a navigation screen, so it is the obvious place to bring up the backup image.

A couple of important considerations regarding the camera itself, beyond the obvious quality. The fact that it produces a mirror image, so that what you see on the right side of the screen is on the right side of the car and visa versa, making for logical avoidance maneuvers. The camera should also have low LUX capabilities, in simpler words; night vision.

The grimmest detail to have to articulate, is a reminder of the number of small children that are accidentally backed over every year. A back up camera that avoids this once, is worth a lifetime of gratefulness.

Cameras tied into the navigation screen, range between $1,000-$1,800 installed on most vehicles.