Unlike the crime of assault, battery requires that actual contact be made, while assault charges can be brought with only the threat of violence.
The laws regarding batter vary from state to state, but many jurisdictions have different classifications or degrees of battery. Simply battery is usually any form of unlawful contact, while criminal battery means there was an intent to cause injury, in some states.
In some states, sexual battery is any non-consensual touching of the intimate parts of another person, but in other states a sexual battery charge requires actual oral, anal, or vaginal penetration.
Aggravated battery results when violence against another results in serious bodily injury or disfigurement. In some states aggravated battery can be charged only if the intent to do serious bodily harm can be proven.
In an effort to cut down on domestic violence, many states have passed family-violence battery laws, which require that cases of family violence be adjudicated whether the victim decides to "press charges" or not.