KIWI GPS navigation system
The KIWI GPS navigation system is used in various in-car systems factory-installed by automotive manufacturers. Variations of this format have been reported for Volvo and Lexus cars; they're probably used in other makes and models as well. Quite a number of variations exist, so you need a navigation update specifically approved for your particular model. They generally come on DVD, and can cost as much as $200 or more, with an additional fee for installation (the dealer apparently has to do something more complicated than just sticking a DVD into a drive within the car). If you resist this expensive upgrade, you might find that when you're driving on relatively new roads or in newly-built developments you are shown as being in the middle of nowhere with no road in sight because the road you're on isn't in the outdated navigation files you have. Or you could pull out your smartphone and see up-to-date info for free on Google Maps or Open Street Map... your choice.
The main files on the navigation DVD have a .kwi extension (there are also a few other files, such as .bmp files that don't seem to be in the normal Windows BMP format, and a few other files). They are in a proprietary binary format, which some hobbyist experimenters have made attempts to decode.