I think I can answer that, although I’ve never actually seen it explained, so it’ll be interesting to see if anyone else has a different take.

The Lemmy posts with “rule” in the title are all made to the 196 community. Per the sidebar, rule #1 of 196 is “you must post something before you leave.”

Putting “rule” in the title is basically shorthand for “I don’t have anything specific to say, but I have to post, so here’s some random shit I find funny.”

At least, that’s how it started. At this point, it’s evolved into a bit of a meme in its own right.

I’m just gonna leave this right here: https://shop.m5stack.com/products/m5stack-dial-esp32-s3-smart-rotary-knob-w-1-28-round-touch-screen

After explaining the destructive force of a single raindrop over a kilometer in diameter:

Fear reigns supreme as the world fears rain supreme

Poetry. True poetry.

Relevant XKCD