California residents who drive on public highways or in public parking facilities must have a California driver license.
Residents : When you become a California resident or take a job and you want to drive in California, you must apply for a California driver license within 10 days.
Non-residents : If you are a visitor over 18 years old and hold a valid driver license from your home state or country, you may drive in California without getting a driver license as long as your home state license remains valid.
Minor Non-residents : If you are a visitor between 16 and 18 years old, you can drive with your home state license or instruction permit for only 10 days after arriving in California. After the 10 days, you must either get a California license or a Nonresident Minor’s Certificate.