For over a hundred years people have been using toy soldiers for advanced sessions of wargaming, but after the advent of Dungeons & Dragons in the 1970s new styles of tabletop play that incorporated more outlandish characters and fantastical narratives grabbed the imaginations of gamers and nerds across the world. Of those tabletop systems the most cultlike and loyal fans belong to Games Workshop's Warhammer 40,000 which updated classic fantasy tropes with a sci-fi setting and so much raw testosterone that playing one game could make your voice deeper. Hulking space marines and rabid orks, legions of absurd ships and vehicles, and factions battling countless counter-factions all contained in a dense lore spanning millenia.
Still confused? This video MIGHT help:
Here's 25 Warhammer 40K memes that are worth more than a fully-painted Imperial Dreadnaught miniature.: