For those of you who don't frequent Tumblr or 4Chan—or, in other words, have a life!—here's what's going down between the two:
In A.D. 2014, war was beginning. What happen? Somebody set up 4Chan the bomb. Then they get signal. Main screen turn on. It’s Tumblr: “How are you classy neckbearded gentlemen!! All your base are belong to us. You are on the way to destruction. You have no chance to survive make your time. Ha ha ha!!!” Then 4Chan take off every Zig. They know what they doing. They move zig—FOR GREAT JUSTICE!!!
Here’s a more accurate, if not more humorous, explanation from InternetAristocrat: