Okay, I’m old…
What’s the difference between “# what a jerk!” and “what a jerk!” What’s going on here?
There’s a pretty straightforward description here.
In a nutshell: it tags things for searching and makes it clickable.
Putting #thingy in your tweet causes Twitter to make the word “thingy” a link to all other tweets wth #thingy in it. It is a way of creating a category of tweets from many users about a topic.
That’s what it’s supposed to do, that was the original idea, that’s certainly not what it’s used for.
For example:
Can’t believe it’s my birthday today. #34Today #ImSuperOld #Geezer #GetYurDrinkOn2Nite
No one is searching for those things. If you click on them you’re probably only going to find my tweets (or FB post as the case may be). They’re basically just used as sort of sum up your post.
I will give it that it’s still works for ‘important’ things. People will tag newsworthy events and it makes it easier to find them on Twitter, especially if the newscasters tell you what to tag them with.
It’s broader than newscasters; it’s the entire crowd effect, especially with influential “trendmakers”. If a twitterer with a lot of followers puts up a hashtag, there are bound to be a lot of followers who respond in their own tweets with the hashtag as well, and the subject builds up an organic presence and its own weight.
And that’s why hashtags matter in the twitterverse. They grow like memes and provide natural instrumentation for popular trends and the people who follow them.
It’s all very insidious: tweeters are creating their own marketing demographics by tagging their own interests-of-the-moment.
And no, I don’t do Twitter. This is just how it’s been described in the nigh-unavoidable technical press about it.
It’s not a “hashtag.” It’s a pound symbol.
#getoffmylawn
Well, once you append the tag text to the pound symbol, it becomes a hashtag (rather than just a hash symbol).
All: Got it! Thank you! I actually understand this! It makes sense, in all the ways described. I like the virality and vitality of it all. It also sort of rewards celebrities with unusual names. Tagging “Smith” isn’t as much fun as tagging “Beyonce.”
Rachellelogram: Ah, the joys of a changing language! I’m old enough to know “.” as a “period,” not a “dot.” But there you have it.
(Pound symbol? It’s an octothorpe! 
)
Octothorpetag doesn’t quite roll off the tongue.
It’s the hash symbol. Or the number sign. Or the octothorpe, though apparently that’s a recent name for it.
The pound symbol is “lb” (or “£”). I don’t know why America chose the # to represent “pound,” it seems unnecessary and complicated when there was already a symbol available for it, and the hash already had numerous other unconnected uses.
Hashtags serve two purposes. One is to associate tweets under a shared topic, such as something in the News or a TV show everyone is collectively watching, but it is also a great way to do an aside, a wry self commentary.
As an Old Person, I have found the non-technical, semantic use of the hashtag becomes more understandable if I mentally read it as “File this under”.
It is also, surely, because that symbol is on a mobile phone keyboard.
No, this is a pound symbol: £
When I encounter someone who gets grumpy about “dot,” I remind them that they probably already know at least two names for that symbol. In English class, it’s a period, and in math class, it’s a decimal. So, here in computer class, we call it a “dot.”
It’s only an octothorpe on a telephone keypad! Otherwise, it’s either a number sign or sharp sign (or symbol, for either of these). Or pound sign, but that’s a pretty rare usage.
It reminds me of the first time I heard a computer talk, in 1975, using the Votrax system. The “#” was the Michigan Terminal System prompt, which I mentally read as “number-sign”. When the odd Votrax voice said “pound-sign” in its odd accent, I couldn’t understand what it was trying to say for the longest time before the light bulb finally came on. That was also when I learned that some folks call “#” a pound sign.
In math class, it should be called a radix point or a decimal point, but not a decimal. “Decimal” is an adjective, properly speaking. (Of course, it has become a noun, as all English words seem to, but even then, it means the fractional part, not the dot. And you kids, get off my lawn!)
Well, the sharp sign is technically a different glyph. It’s only when you don’t have it available that you substitute the pound/hash/number/octothorpe. Here’s a music sharp symbol: ♯. Here’s the pound symbol: #. Note that in the sharp sign, it’s the horizontal bars that are slanted, and in the pound sign, it’s the vertical bars that are slanted.
Also likely is that the person complaining is old - ask them if they know any Morse Code…
Hashtags have become meta-commentary, much in the same way that messageboard posters will use asterisks or italics to set something off as a description.
munches carrot thoughtfully while arranging visionboard
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