Infraction traffic tickets
If the police stop you for driving too fast or running a red light, they can charge you with an infraction and give you a "Notice to Appear" ticket. If you don't have proof of your car insurance, you'll be charged with an infraction for driving without proof of insurance.
Misdemeanor traffic tickets
The police can give you a ticket for a more serious crime, like driving without a license. If the charges don't involve alcohol or drugs, the police officer can ask you to sign the ticket, also called the "Notice to Appear." Signing doesn't mean that you admit you're guilty. It just means that you promise to appear in court.
If the police officer thinks that you're driving under the influence of alcohol and/or drugs, you'll be taken into custody.
http://www.courtinfo.ca.gov/selfhelp/traffic/info.htm