Development of the banknote began in the Tang Dynasty during the 7th century, with local issues of paper currency, although true paper money did not appear until the 11th century, during the Song Dynasty.
A contract typically does not have to be notarized. A notary public (or simply notary) provides an acknowledgment that the signature appearing on the document is that of the person whose signature it purports to be. There is a requirement that some documents be notarized, such as a real property deed.
However, a deed requires some additional execution formality beyond a simple signature. Deeds must be in writing and will typically be executed in the presence of a witness, although in the case of a company a deed may be executed effectively by two directors or a director and the company secretary.