A notary is a person who is authorized by the state, typically to witness or certify the signing of documents. The notary has to first be sworn in before they can start signing documents and certifying their validity. The responsibilities of a notary public vary from one location to the next. For example, in California, some duties include: reviewing for accuracy, witnessing and certifying sealings and authentications of court pleadings and other legal documents after reviewing them for accuracy. Some also provide formal acknowledgments for affidavits that are submitted as evidence in court proceedings on behalf of another party (for example, a corporation). In addition, some states require that when a document is notarized there be two witnesses present with valid identification at the time of signing.