Energy and energy resources are among the most important feedstocks of economic development, national security and welfare.

Oil and natural gas (together) provides 55% of the primary energy the world consumes (as of end 2023). TUnderstanding the geographic distribution of crude oil and natural gas reserves is vitally important for every engineer working on energy related concepts and especially for petroleum and natural gas engineers. Together with the geographic distribution, how much hydrocarbon each country produces, how much they consume, the international trade, evolution of prices are also significantly important parameters to better understand the world events. All the wars (World War 1 and 2, as well as the ongoing proxy wars are wars for capturing and controling the energy resources, their transportation routes and trade. Every engineer should have scientific and updated information on these subjects.