This article is from the California Driving (and Surviving) FAQ, by "George J Wu" email@example.com with numerous contributions by others.
from the Spring 1991 DMV California Driver Handbook:
California's COMPULSORY FINANCIAL RESPONSIBILITY LAW requires every DRIVER
and OWNER of a motor vehicle to maintain financial responsibility. There
are four forms of financial responsibility:
o Coverage by a motor vehicle liability insurance policy [of at least
o A deposit of $35,000 with DMV.
o A bond for the same amount (although generally bonds are unavailable).
o DMV approved self-insurance.