There are certain little symbols we use to enhance our written communication. For example, that sentence ended with a full stop (called a 'period' in the US). These 'dots' are used to signify the end of one thought and the start of another. But, in our fast-changing world, some punctuation marks seem to be evolving, while others look as though they may disappear altogether.
I heard an ad for Money Supermarket on the radio the other day, whether the voiceover included the expression: "Hashtag epic". Yes, he actually spoke the word "hashtag". I've seen trendy young presenters on TV say things like: "Hashtag just kidding" while crossing over the first two fingers of each hand to make the symbol.
It put me in mind of the time I overhead someone on the phone listening to a recorded message. "What the ****'s the hash symbol?" he exclaimed in annoyance. That was probably about a decade ago. Nowadays, I doubt there's anyone who isn't aware that the hash (number) sign is the one that looks like the start of a noughts-and-crosses / tic-tac-toe game. But maybe there are still a few people who don't know how it's escaped from the keyboard* and into the spoken word.
Think of the index in a book. It lists key words that have been used and the pages where they appear, so as to make it easy for readers to navigate their way to any mention of the word.
With content now being produced online rather than on paper, the concept of 'tagging' is equivalent to the index. A blog post like this one is 'tagged' with keywords to help readers find other posts with the same tags. It also helps the post to be found on search, because tags are clickable links and search engines therefore think they are important.
From blogging, we move to micro-blogging, and Twitter in particular. If you want to tag your tweet i.e. make a word a clickable link to other instances of that word, you precede it with the hash symbol (no spaces). Hence, hashtag.
Certain hashtags have quickly become popular e.g. #Fail #EpicFail #JustSaying #JustKidding #TwitterTips.
Just as many of these have escaped from Twitter onto Facebook and other social media sites, they have moved from the screen into our spoken language, and now, the adverts.
Along with the rise of the hashtag, we seem to be losing other punctuation marks, probably because all those dots, dashes and squiggles are too tricky to text. But that's a topic for another blog...
*Note there is no 'hash' symbol on a Mac keyboard, you have to type alt+3.