'At' - the two-letter combination originates from humble beginnings as a simple word that required a quick couple hits to the computer keyboard. I grew up knowing when to use 'at' within a sentence (but never at the end of one). The tiny word stayed out of the limelight and didn't get a whole lot of attention - until the pint-sized preposition made the transition from word to symbol and suddenly @ was the place to be.

I'm guessing we all possess at least one @ and access it on a daily basis. Email practically owes its existence to the curlicue, lowercase A.

In a logical, natural and symbolic way, @ gives each of us a location of our own. Being someplace is critical to one's existence. If you're not @ somewhere you are nowhere - which is the opposite of @ - and I don't have any idea where that might be.

I figured I had it figured out. I knew where I was @ and lived in comfort right there. Recently, however, I learned there may be something even more important than being @ somewhere, and that's where you're headed.

We're all @ our current location, but to go beyond requires a symbol all its own - the hashtag (#). You may be more familiar with Mr. Hashtag as the number symbol, pound sign or a tic-tac-toe board. He's all those things, but now he's got a more important job - over @ the Twitter.

Online, within a social media site, users type a hashtag before a relevant keyword or phrase (without spaces between words) to mark it and link it to similar phrases. According to my friends at Wiki, hashtags function as beacons, drawing users with similar interests together - like fruit flies to a banana. When a whole bunch of users swarm toward a certain hashtag, the topic is said to be trending.

Trending, my friends, is the new cool.

My introduction to the world of hashtags happened quite unexpectedly. As a mom to multiple teenagers, I hardly ever say anything relevant. It's the main reason I talk to myself. I am the only one who will listen.

Except for last Tuesday when I made a witty (and apparently relevant) observation when I said, "I think it would be fun to go into (a well-known fast food restaurant) and order two Shamrock Shakes and one Harlem Shake."

This Twitter-worthy statement got me noticed by my social media-posting teens and warranted my first-ever hashtag (#HipsterMom). Before you could say, "re-tweet" I was trending like a pop star (#JustinBieber). People were promoting my comment like it was a beacon - or maybe a ripe banana - and I found myself hooked and hungry for more.

You know how it goes with trends. They fade faster than a flashlight battery, teen pop star or over-ripe banana. I had to come up with another relevant comment if I wanted to stay on top of the trending cesspool of #HipsterMoms.

My next gem took the form of a science-related question. "What do you get when you combine oxygen with magnesium?" The answer (wait for it...): "OMG" (LOL).

With my newest insight, I figured I'd be @ #HipsterMom status again in no time. It felt good to be a beacon, but of course I couldn't keep it up forever. Not even Justin Bieber can do that.

I may be a hashtag has-been, but I appreciate the power of cyber symbols and am grateful to be hipster enough to know where it's @. I look forward to the cyber future with glee (#Optimism) and can hardly wait to see what they do with the ampersand.

- Jill Pertler's column appears every Thursday in the Times. She can be reached at pertmn@qwest.net.