As a fairly early adopter of the internet and computers, going back to the 1980s, I’ve always thought I had a pretty good handle on what it is like to live a life saturated with technology from early on.

There aren’t many of my generation, beyond some business, research and academic users, who can say they were using the net before there was a World Wide Web – those of us who experienced the exhilarating, mind-blowing ride of the internet’s early development, from command line interfaces to the whole smorgasbord of interactivity we have now.

But this gives little insight into what it means to be an online teenager today. Until recently, I naively presumed I got it. Then, I began really listening to some teenagers, and realised I just cannot know what it is like to grow up either as a millennial (the 18 to 25 age group) or the next generation coming up. These are the first two generations to have always known the internet.

As anyone with a teen around the house knows, they are always online, and always on. Maybe you (presuming you are older than this) think: “Well, I am too – so what?”

But you aren’t online in the same way, because you are older, and as an adult, know more about who you are. You have adult friendships and jobs.

You might still be – and hopefully, are – on that lifelong journey to a strong sense of self. You’ve studied, you’ve worked, you probably have had a few relationships that were long-lasting, you might be settled, with a loving partner or spouse, perhaps with children of your own.

You have probably travelled, maybe even widely. You’ve known rejection and recovered from it or learned to live with it. You’ve discovered music and writers and artists, sports and science, a hobby.

You probably use social media to post about some of these things in your life. Maybe you offer your opinions and ideas. Maybe the experience hasn't always been a good one – you've suffered from putdowns on Twitter, perhaps, or rudeness on Facebook.

But none of these things gives you much insight into what it is like to be a teen, to have this all around you, all the time, during this critical stage in the formation of self. When you may be confident, but you are also deeply vulnerable. When you are acutely aware of everyone else around you, and what they think, and whether you fit in.

More exposed

You embarrass easily. Though you think you aren’t, or try to hide it, you are rawer, and more exposed, and sway this way and that in response to influences, good or bad. You say and do things that you think you need to do to fit in. Not even to be popular, but maybe just not be noticed as someone who (apparently) doesn’t fit in.

We get older. We overcome and we forget these things.

But it came back when I heard an older teenager say recently, with the open eloquence of youth, that she fears she will become the adult dictated by her social media profiles, without ever learning who she actually is.

I was floored.

That was the moment that I realised those of us who came to the internet and social media as adults, just cannot really understand this. This challenge; this potential tragedy.

I use social media just about every day. I use it with privacy in mind. I think about public perception, because I know a lot of followers are there because they know me from my job, not necessarily personally. But none of this enables me to walk in the shoes of a 17-year-old with an always-on, complex, scrutinised, self-censored, passionate online life.

A recent article about teenagers and app and social media use, which we carried in The Irish Times Innovation section on Monday ("Growing up mobile: app dings and pings become soundtrack of millennial youth"), might help all of us that bit older to begin to understand.

Personal PR

They are acutely aware of what they post, how they are seen, whether posts are liked. They will self-censor and delete, out of embarrassment and shame. It’s constant personal PR, a management of their developing self.

"They have immediate social validation or lack of validation at the touch of a button," notes Michael Jones, chief executive of a company called Science Inc which develops social media apps.

Think about that.

I’ve no idea what the long-term implications are, of this kind of instantaneous watch-and-be-watched world, or even the short term pressures – for many, the misery – this must place upon teenagers.

But we as a society, and as developers of such services, do need to think about this.

No one should have to grow up to be a person defined by their youthful Facebook posts.