Redditors are using computer code and a niche reference from one of Terry Pratchett's books to make sure his name lives on forever.
This term derives from the fantasy author's Discworld series of books and specifically the story of character John Dearheart.
When Dearheart died in the book, other characters ensured that his soul continued "living on in the overhead" by sending a code around their communication system known as the "clacks".
As explained in this thread, a message would consistently appear in the clacks with a piece of code followed by a name - GNU John Dearheart.
G means the message must be sent on, N means the message is not logged and U means it must be returned when it reaches the end of the line.
In the book, the character Princess asks Grandad: "So it's just a name, going up and down all the time! Where's the sense in that? Who's John Dearheart?"
The thread continues:
"He... fell off a tower," said Grandad. "Hah!" said Roger, working his shutters as if he suddenly hated them. "He's dead?" said Princess. "Well, some people say—" Roger began. "Roger!" snapped Grandad. It sounded like a warning. "I know about Sending Home," said Princess. "And I know the souls of dead linesmen stay on the Trunk [one of the clacks]."
"Someone was trying to scare you," said Grandad, looking at Roger's reddening ears. It hadn't sounded scary to Princess. If you had to be dead, it seemed a lot better to spend your time flying between the towers than lying underground. But she was bright enough, too, to know when to drop a subject.
It was Grandad who spoke next, after a long pause broken only by the squeaking of the new shutter bars. When he did speak, it was as if something was on his mind. "We keep that name moving in the Overhead," he said, and it seemed to Princess that the wind in the shutter arrays above her blew more forlornly, and the everlasting clicking of the shutters grew more urgent.
"He'd never have wanted to go home. He was a real linesman. His name is in the code, in the wind in the rigging and the shutters. Haven't you ever heard the saying: 'A man's not dead while his name is still spoken'?"
And now, thanks to Redditors embedding this code into "the wind, in the rigging and the shutters" of the internet, Terry Pratchett will live on too.