When you sue a person, company, or the government, you must give notice to the other side that you have started the legal process. Or when you are already involved in a case and file papers with the court, you are required to give the other side notice of the paperwork that you have filed.
The legal way to give notice is to have the other side served with a copy of the paperwork that you filed with the court. This is called service of process.
Service of process means that the other side must get copies of any papers that you file with the court. In service of process, a third person (NOT you) is the one who actually delivers the paperwork to the other person or people involved in the case. The person who gives copies of court papers on your behalf is called a server or process server.
Until the other side has been properly served, the judge cannot make any permanent orders or judgments.
Once you have completed service, you have to prove to the judge that you did it. If you cannot give the judge proof of service, your case will be dismissed.
If service was made by the county sheriff, the sheriff's deputy, or a process server, then you can get proof by getting a certificate of service or return.
If you made service by mail, then you have to attach the return receipt and the envelope to the Affidavit of Proof of Service. This affidavit is a sworn statement that you file with the court that says that you've provided service to the defendant.
Service must be made within 120 days after filing your court forms. If you cannot give the judge proof of service, your case will be dismissed.