People have only just found out what the H on lampposts means

Sometimes it can be the most common, mundane things that we don’t actually know the use of.

Sure, we’ve got all this obscure knowledge of random gadget or technology we’ll never get our hands on, but we’ve only just realised why there’s dots on the car we get in every day.

And despite probably walking past them hundreds of times, not everyone knows what those H signs on lampposts mean. You know the ones, those yellow signs with the big letter and two numbers at the top of the bottom? No idea what they’re used for though.

People have had all kinds of theories about what the H could stand for, with some suggesting helicopters.

To be fair, that seems reasonable at first but why would helicopters make a habit of landing in the middle of residential roads?

"Oh dear, not me thinking hospital close by," another said on TikTok.

Others simply don’t care either as one wrote: “It’s nowt to do with me so I just walk on by. What do I need to know for?” And fair enough, I guess.

However, the curiosity has built up for a lot of us so let’s uncover what the mysterious H signs actually mean together.

South Yorkshire Fire posted a video on TikTok, saying: "POV: You’ve walked past these small yellow signs your whole life."

"But it was today you realised, finally, after all these years, they are there to tell firefighters where the hydrants are."

You read it right, the big H's show fire fighters where the water supply is, as sometimes the fire hydrant cover is obscured. Some people were adamant that they’d always known, saying they’d been taught at school or that it was simply ‘pretty obvious’. Sure.

But many admitted it was brand new information, with one saying: "I never knew. Everyday is a school day thank you."

Someone else said: “Well I learnt something new today thank you!"

Some TikTokers also asked what the numbers meant above and below the H.

According to Hydrants Direct, a company that maintains and tests privately owned fire hydrants, local authority fire and rescue services are usually responsible for the hydrant signs.

The website explains: "The location of a fire hydrant is indicated by an above ground post or marker plate. Hydrant marker plates are rectangular yellow signs, with a large black H and a pair of numbers, usually attached to a wall, lamp post or a short concrete post. The two numbers on the plate show the size of the water main and the approximate distance of the hydrant from the plate. Yellow paint is sometimes used to help identify a fire hydrant cover.

"As well as marker plates, all hydrants are also shown on the digital maps available in fire engines, so that the nearest one can be found while firefighters are on their way to an incident.

"This also means that even if marker plates are missing or broken, the fire service will still be able to find them in most cases, and once reported they will be repaired in due course."