What is Apostille?
Think of apostille as notarization that is internationally recognized. When you get your documents notarized in your home country (domestically), they are only recognized in that country. With apostille, your documents will be recognized in countries that signed the Apostille Convention.
For example, if you want documents like your birth certificate or marriage certificate from the United States to be recognized in Armenia, you must apostille them where those documents were issued. Because the United States and Armenia are signatories of the Apostille Convention, the documents with apostille you bring from the U.S. will be recognized as official documents in Armenia.
This can make your life much easier when trying to get translations to apply for residency, citizenship, or any number of other things requiring official documentation.
See if your country is a signatory of the Apostille Convention here.
Apostilles are issued by the Registry Offices of the Ministry of Justice in Armenia. You will need to send in an application, the original and a copy of the documents requiring the apostille, and a receipt of payment (7,000 AMD to state account number - 900005163523). Unless rejected, it is issued within 2-5 working days (there may be delays up to 15 days, but you will receive a notice with reasons as to why), though there is an accelerated version for applications received before 13:00. In this case, combined with the extra payment (an additional 8,000 AMD or total of 15,000 AMD), you may receive your apostilled document back the following morning from 10 am. Anyone can apply for an apostille. More information is available here.