So just what is the “#” symbol to you?

An interesting question yesterday came up, what is the “X” symbol called.

Well I actually knew it as 4 names, the number sign, pound symbol, octothorpe and hashtag.

I had thought the octothorpe was the original name, but when I looked it up I was wrong.  I learned the octothorpe from my working days in telecommunications as it was a name given to it by Bell Labs likely in the 1950’s, but it was around and known long before that.

In fact it was on typewriter keyboards since the late 19th century and was in common use and known as the number sign.  Now most of those reading that can recall this likely.

But even before that, dating back to very early times into the Roman era, it was originally known in Latin as the libra pondo, meaning “pound in weight”.  This is actually where the abbreviation of “lb” came for pound.  So apparently the very early use was for pound!  How many remember it being used for pound?

It has apparently had many other titles, many of which I was unaware, over the years but I am only referencing the most common and those I was familiar with.
Other than the pound sign it was also known as “cross-hatch” or “hash” as an abbreviation for “cross-hatch”.


Chess users have also used it to symbolize “checkmate” as a move.  And of course it is the musical “sharp note”.

And of course beginning with Twitter around 2005 it began the journey as being a “hash tag”, which is on many or most social media platforms today.

Interestingly enough when introduced on Twitter originally it was something people though kind of geeky and only for “nerds”.    In fact when first suggested by Chris Messina, it was not something favoured by the rulers of the Twitter platform.  It did however slowly catch on and become popular and has spread across virtually every social media platform over the past decade.

So what name do you know it by?  And were you surprised that it is not a rather new invention but has been with us for a couple of millennia?

Don’t you just love #History.

Author: Chimney Sweep

WETT Certified Advanced Chimney Sweep - Loving It Every Day