California Penal Code Section 240 covers "assault," which is the willful attempt to inflict bodily harm on another person; while PC 242 covers "battery," which is an assault carried through to the point that bodily contact of any kind is made with the victim.
Simple Assault is a misdemeanor, punishable by 6 months in county jail, a maximum fine of $1,000, summary probation, and full restitution to the victim. Battery can be either a misdemeanor or felony. As a misdemeanor, it is punishable by 6 months in jail, a $2,000 fine, formal probation, and full restitution. As a felony, it is punishable by up to 3 years in jail/prison, and a fine of from $2,000 to $10,000.
If aggravating circumstances such as use of a "deadly weapon," infliction of "serious" bodily injury, or causing the death of the victim are involved, punishments are correspondingly more severe.
Important defense strategies include: The defendant acted with the consent of the victim and without intent to harm him/her, the actions were accidental and thus not assault/battery, and the defendant was acting in self defense or in defense of another person.