What’s an apostille?
Apostille is endorsement of an official document (such as a birth certificate) for international use. It’s usually a stamp, although it may be a separate piece of paper. Only certain countries issue apostilles.
Where do I get one?
Apostilles are issued by the office/authority, which issued the original document. In the United States, apostilles are usually issued by the local Secretary of State, which issued the document that is to be certified.
Why do I need one?
Many countries, incl. Czech Republic, do not recognize official documents issued by foreign countries, unless they bear apostilles.
Which countries issue/accept apostilles?
Most Western, incl. all EU member countries issue and accept apostilles, with the notable exception of Canada.
You may find an up-to-date list of countries here.