When I was a kid in the 1970s there were no computer games so for fun we'd climb trees, swim in rivers and practise Evel Knievel jumps on our Raleigh Choppers – with about the same level of success as he had.

When even those pleasures paled we'd set our minds to unravelling the mysteries of the universe. Such as why the Wombles theme tune contained the line "common are we" and why the zips on our flares bore the same mysterious three letters: YKK. Was it code? Did it really stand for "You knob, Kev", as some argued?

This year marks the centenary of the zip, or zipper as the Americans call it, though it's to Japan that we have to turn to learn what YKK means. It's the trademark of the Yoshida Kogyo Kabushikikaisha company, founded in 1934 and today not only the world's largest manufacturer of zips but also a maker of specialised kit for the architectural profession. So now you know.

Although the Automatic Continuous Clothing Closure was patented in the US in 1851 by Elias Howe, inventor of the sewing machine, the zip as we know it came into being in 1913 when Swedish-American designer Gideon Sundback finally perfected Howe's original technology. Sundback called his version "the separable fastener", which meant it took longer to say its name than it did to do it up. But when the fastener was adopted by industrialist Benjamin Goodrich for use in a range of rubber boots, the name by which they were known – zippers – proved perfect for Sundback's invention too. And so it stuck, as zips done ever since.

The only other thing Goodrich made was tobacco pouches so it took a while for the buttoned-up world of fashion to cotton on to the possiblities of the zip. By the 1930s they were appearing on children's clothes and by the late 1930s they were adopted where they were needed most – on gentlemen's flies.

Fast forward a couple of decades and they were de rigeur in men's tailoring, except perhaps in the most traditional of Savile Row establishments. But even our old friend Hardy Amies was coming round to them by the time he penned his ABC Of Men's Fashion in 1964.

To Amies's experienced eye, zips made "a great contribution to the comfort and appearance of trouser fronts by doing away with buttons which are inconvenient and bulky". But he also noted that as nobody knew how they actually worked people were "wrongly suspicious" of what was otherwise "an excellent invention".

Still with what Amies coyly calls "trouser fronts" there was a word of warning, however. Excellent the zip may be, "but you still have to be careful", he added. Wise words from a man who'd never even seen There's Something About Mary. But let's not let the danger of genital mutilation detract from what is otherwise a very creditable century of use. Happy birthday, zip.

barry.didcock@heraldandtimes.co.uk