In South Africa only a Notary Public can notarise documents. A notary Public is an attorney that has the additional qualification of being a Notary Public. A Notary Public has to pass the Notaries examination and be admitted by the High Court of South Africa to practice as a Notary.
Notarised documents can be used in South Africa and overseas and carry a certain level of authority. In South Africa some institutions such as the HPCSA (Health Professions Council of South Africa) will insist that documents are notarised or signed in the presence of a Notary Public.
Other countries may also insist that university or school qualifications, ID documents, marriage certificates and so on are notarised before they will accept them for use in their country.