How do you drive this thing? The way out of Twitter...

Not everyone will have this memory, but bear with me. At some point, during the final goodbyes of awkward schooldays, a friend within an immediate circle of friends will pass their driving test and get regular access to a car. It will be exciting for many, not least the person who now has a spanking new driving license. The novelty will be there, coupled with the genuine excitement of travelling to places you don't normally get to travel to. There's also a brand new boisterous litter of eager faces, loitering at each new destination. Suddenly, geography is no longer binding frustrated gregarious gaggles to one tiny location.

One by one, more friends get cars. All of them have different ideas about where they want to go. But because each and every one of them is a friend of yours, you're happy to go along for the ride with them. It's about the journey, isn't it? It's about exploration and extending possibilities and endless landscapes, right? Then, one day, an amazing friend, someone who you've seen through thick and thin, someone who you've seen sit stressful exams and suffer break-ups, someone who you've seen grounded by immediate family, shows a whole new dimension to their personality.

"Get off the fucking road, dickhead!" screams that relaxed, amiable, laid-back friend of yours. The transformation is as quick as the conversion back. "Anyway," says Mr Laid-Back, "how are you? What was that book you're reading again?".

It's a shock. This friend of yours is still undeniably a great friend and one with a great deal of wisdom. Get that friend behind a steering wheel, however, and they turn into a Grade A, Class 1, 100% asshole with distinction. It gets worse though. You now realise that, after a while, everyone is driving around shouting obscenities at each other. In fact, the bigger the vehicle and the more numerous the passengers within it, the bigger the boldness of each driver. There seems to be less recognition that each bland vehicle might contain human beings in there. Everyone is blind to each other. It's almost as if everyone is now just a darkened windscreen and treating each other that way.

I'm in my car now. I'm following a small selection of people. They don't behave like egotists behind a steering wheel, surely? I recognise their driving license plates, because I've been following them for ages and they've always guided me down dark lanes and around unfathomable spaghetti junctions. In the last fortnight, however, the identifying license plates might as well belong to any car driven by a random road hog . All those cars that I follow appear to be being driven angrily, or aggressively, or patronising other drivers who don't know the route as well as them.

I'm remembering when I passed my driving test. The feeling was immense. All those small corners of the peninsula to explore. The sweet baked bread smell of a Summer, getting in another friend's car to just enjoy the journey they took you on. Before they began to get angrier and shouting abuse at other drivers. It's now got to the point where someone will bawl at a stranger for not moving off quickly enough within the split second that a traffic light changes colour.

I've slowed down now and decided to just get out the car. I've also realised, through a muggy embarrassed memory, that I've rolled down the passenger window on a number of occasions and shouted at the odd person. The novelty has worn off. It's time to just mothball the vehicle and park it in a side street. Forget it for a while. I'll head home and enjoy walking in the last rays of an Autumn sunshine for the next few weeks. Until I have to start using the car again and have to scratch the frost off the windscreen.

I'm home now. Alone. I switch the computer on.

What's this Twitter that everyone is on about?