A notary public acts as an official, unbiased witness to the identity and signature of the person who comes before the notary for a specific purpose. The person may be taking an oath or signing his / her signature on a legal document. 

A Notary Loan Signing Agent or Certified Signing Agent is a notary who guides someone through the signing of their loan closing papers, making sure they sign each document properly, and then notarizing the documents that require a notarization. They are often mobile notaries who are sent to the borrower’s home or office with the loan papers, saving them a trip to the title company during office hours.