Socket map of the world

• The ‘American’ model (yellow), consisting of two vertical rectangular openings, side by side...
• The ‘subcontinental’ model (dark green), a triangle of circular openings...
• The ‘antipodean’ model (light blue), made up of three rectangles arranged to look like the mask from the Scream movies, is used in only four countries, all in the Southern Hemisphere: Argentina, Australia, New Zealand, and Papua New Guinea.
• The ‘imperial’ model (dark blue), two flat rectangles below, one upright on top, quite clearly is a remnant of the British Empire, as it is used not only in the UK and Ireland, but also in that swathe of Africa with which Cecil Rhodes had once sought to connect ‘the Cape and Cairo’...
•  The ‘European’ model (light green), which looks a bit like Wall-E...

An important note at the Big Think source: "This map, sent in by Mark Lakata, was first published in National Geographic. It chooses clarity over comprehensiveness: in reality, there are 13 plug-and-socket systems in operation throughout the world (some are compatible with each other), and numerous national standards for voltage and frequency.