In the family of punctuation, where the full stop is daddy and the comma is mummy, and the semicolon quietly practises the piano with crossed hands, the exclamation mark is the big attention-deficit brother who gets overexcited and breaks things and laughs too loudly.

Many aspects of our screen-bound lives are bad for our social skills simply because we get accustomed to controlling the information that comes in, managing our relationships electronically, deleting stuff that doesn't interest us. We edit the world; we select from menus; we pick and choose; our social 'group' focuses on us and disintegrates without us. This makes it rather confusing for us when we step outdoors and discover that other people's behaviour can't be deleted with a simple one-stroke command or dragged to the trash icon.

Punctuation marks are the traffic signals of language: they tell us to slow down, notice this, take a detour, and stop.

All writers learn this, in time: don't show your work to other people until it's safely finished. Even discussing your unborn book in quite general terms can be such an undermining experience that, afterwards, you give it up and go to live in Guatemala.

I mean, full stops are quite important, aren't they? Yet by contrast to the versatile apostrophe, they are stolid little chaps, to say the least. In fact one might dare to say that while the full stop is the lumpen male of the punctuation world (do one job at a time; do it well; forget about it instantly), the apostrophe is the frantically multi-tasking female, dotting hither and yon, and succumbing to burn-out from all the thankless effort.

As someone who sends texts messages more or less non-stop, I enjoy one particular aspect of texting more than anything else: that it is possible to sit in a crowded railway carriage laboriously spelling out quite long words in full, and using an enormous amount of punctuation, without anyone being aware of how outrageously subversive I am being.

The idea of withholding a massive secret is obviously quite exciting to some people. It is also the basis of much classic drama, of course, from Sophocles onwards.