A notary public is a state-commissioned official authorized to witness the signing of important documents, verify the identity of the signer, and apply an official seal to confirm the notarization. Notary services in Texas are governed by the Texas Secretary of State, which commissions notaries to perform notarial acts anywhere in the state for a four-year term. 

The purpose of notarization is to deter fraud. When a notary witnesses your signature, they are confirming three things: that you are who you say you are (based on your government-issued ID), that you signed the document voluntarily, and that you appeared to be of sound mind at the time of signing. The official notary seal and signature on the document signal to banks, courts, government agencies, and other institutions that the signing was witnessed by an authorized official. 

Not every document requires notarization — but many of the most important ones do. Legal document notarization is typically required for affidavits, real estate documents, powers of attorney, vehicle title transfers, and many immigration documents before they are considered legally valid.