Probation literally means testing of behaviour or abilities. In a legal sense, an offender on probation is ordered to follow certain conditions set forth by the court, often under the supervision of a probation officer. Offenders are ordinarily required to refrain from subsequent possession of firearms, and may be ordered to remain employed, abide to a curfew, live at a directed place, obey the orders of the probation officer, or not leave the jurisdiction. The probationer may be ordered as well to refrain from contact with the victims (such as a former partner in a domestic violence case), with potential victims of similar crimes (such as minors, if the instant offense involves child sexual abuse), or with known criminals, particularly co-defendants. Additional restrictions can include: a ban on possession or use of alcoholic beverages, even if alcohol was not involved in the original criminal charges. Offenders on probation might be fitted with an electronic tag (or monitor), which signals their whereabouts to officials. Also, offenders have been ordered to submit to repeated alcohol/drug testing or to participate in alcohol/drug or psychological treatment, or to perform community service work.