OPEC (Organization of the Petroleum Exporting Countries) is an intergovernmental organization made up of 14 nations, including IRAN (4 letters), United Arab Emirates (UAE, 3 letters), and Libya (5 letters). These countries are all major producers and exporters of oil and work together to coordinate and unify their petroleum policies. OPEC nations have a significant influence on the global oil market and are responsible for setting production quotas and prices.