NATO, or the North Atlantic Treaty Organization, is an international ALLIANCE of countries from Europe and North America. It was established in 1949 with the signing of the North Atlantic Treaty, which created a military and political PACT between the member states. The acronym for NATO is an eight-letter word, and the PACT it created is a four-letter word. The organization itself is a three-letter word. NATO has been an important part of international security since its inception, and continues to be a major player in global affairs.