H is a number 

A joke that most people don't get that's mostly used in purposes of baiting switch.

H Is A Number (or H-roll) first became a thing on August 13th, 2020 when some users had a general discussion on discord, some people were talking about age restrictions.

"Users under 13 cannot use discord" someone said.

Of course, people were joking about someone being underaged after that message. Another user replied with:

"Age is a number, not a problem"

And that's where the joke basically began...

Some hours later, a user by the name of "undR/H cancer not allowed" posted a morse code that once translated said this:

"H is a number, just got H-rolled"
(There's numerous ones but this one is the most well known message)

From then on, the joke "H is a number" is not just used to warn moderators that users under 13 are on their discord server, but it's also used for morse code conversations, ending with the phrase "H is a number" or "-H" as a joke at the end of the message. Of course it's not just used on discord only, since it's a meme, it can spread from person to person.

Hey, did you know that H is a number ?

H is a number by All77 August 14, 2020

a number on his back 

when you dont have a target on you but everyone knows to stay clear of you

you know darell, they put a number on his back although he weak he still beat a guy with 250 bodies to his name.

a number on his back by gods of corgis February 23, 2023