Apostilles are used whenever public documents need to be produced abroad.
If you have been told that you need to apostille your document, it is because it need this type of verification in order to be valid for use in another country. The Apostille itself is a full page certificate that is permanently attached to the document.
Apostille only authenticates the origin of the underlying public document. Apostilles authenticate the seals and signatures of officials on public documents such as birth certificates, notarial certificates, court orders, or any other document issued by a public authority, so that they can be recognized in foreign countries that are parties to the Convention.
The situations where an Apostille is needed are countless. This may occur in a multitude of cross-border situations: international marriages, international relocations, applications for studies, residency or citizenship in a foreign State, intercountry adoption procedures, international business transactions and foreign investment procedures, enforcement of intellectual property rights abroad, foreign legal proceedings, etc.