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The Treaty of Brussels, signed on 17 March 1948 by Belgium, the Netherlands, Luxembourg, France, and the United Kingdom, is considered the precursor to the NATO agreement. The treaty and the Soviet Berlin Blockade led to the creation of the Western European Union’s Defence Organization in September 1948. However, participation of the United States was thought necessary both to counter the military power of the USSR and to prevent the revival of nationalist militarism, so talks for a new military alliance began almost immediately resulting in the North Atlantic Treaty, which was signed in Washington, D.C. on 4 April 1949. It included the five Treaty of Brussels states plus the United States, Canada, Portugal, Italy, Norway, Denmark and Iceland. Popular support for the Treaty was not unanimous, and some Icelanders participated in a pro-neutrality, anti-membership riot in March 1949. The members agreed that an armed attack against any one of them in Europe or North America would be considered an attack against them all. Consequently they agreed that, if an armed attack occurred, each of them, in exercise of the right of individual or collective self-defence, would assist the member being attacked, taking such action as it deemed necessary, including the use of armed force, to restore and maintain the security of the North Atlantic area. The treaty does not require members to respond with military action against an aggressor. Although obliged to respond, they maintain the freedom to choose the method by which they do so. This differs from Article IV of the Treaty of Brussels, which clearly states that the response will be military in nature. It is nonetheless assumed that NATO members will aid the attacked member militarily. The treaty was later clarified to include both the member’s territory and their “vessels, forces or aircraft” above the Tropic of Cancer, including some Overseas departments of France. The creation of NATO brought about some standardization of allied military terminology, procedures, and technology, which in many cases meant European countries adopting U.S. practices. The roughly 1300 Standardization Agreements codified many of the common practices that NATO has achieved. Hence, the 7.62×51 NATO rifle cartridge was introduced in the 1950s as a standard firearm cartridge among many NATO countries. Fabrique Nationale de Herstal’s FAL became the most popular 7.62 NATO rifle in Europe and served into the early 1990s. Also, aircraft marshalling signals were standardized, so that any NATO aircraft could land at any NATO base. Other standards such as the NATO phonetic alphabet have made their way beyond NATO into civilian use.