If you're not a gamer or have one under your roof or in your family then you're like me! You have to learn from Googling it or hearing about it on television.
It's a multi player game that was released by a North Carolina (USA) company called Epic Games. Here's the gist of it...close your eyes and picture yourself on present day earth Earth (not hard!) now open them and the majority of everybody is gone, evaporated! now .
If you woke up to everybody gone what would you have to do? You'd have to collect everything you need to survive. Right? Shake your head yes. Now, knowing that most people are gone from earth but some still exist you'll need to build for yourself protection. Fortifications.
There ya go. That's the gist of it!
What I understand of it is that most people play the free version but according to numbers generated in early 2018 the games has a minimum 40 million players and generates in-game sales of at least $300,000,000.00 per month.