Service of process is the procedure employed to give legal notice

Notice

Notice is the legal concept in which a party is made aware of a legal process affecting their rights, obligations or duties. There are several types of notice: public notice , actual notice, constructive notice, and implied notice....

 to a person (such as a defendant) of a court

Court

A court is a form of tribunal, often a governmental institution, with the authority to adjudicate legal disputes between parties and carry out the administration of justice in civil, criminal, and administrative matters in accordance with the rule of law...

 or administrative

Government agency

A government or state agency is a permanent or semi-permanent organization in the machinery of government that is responsible for the oversight and administration of specific functions, such as an intelligence agency. There is a notable variety of agency types...

 body's exercise of its jurisdiction

Jurisdiction

Jurisdiction is the practical authority granted to a formally constituted legal body or to a political leader to deal with and make pronouncements on legal matters and, by implication, to administer justice within a defined area of responsibility...

 over that person so as to enable that person to respond to the proceeding before the court, body or other tribunal. Usually, notice is furnished by delivering a set of court documents (called "process

Legal process

Legal process , are the proceedings in any civil lawsuit or criminal prosecution and, particularly, describes the formal notice or writ used by a court to exercise jurisdiction over a person or property...

") to the person to be served.
Each jurisdiction has rules regarding the means of service of process.