Yes, but why?

X tends to stand out among all the letters of the alphabet, doesn’t it, even if it is the third least-frequently used letter. It can represent, the unknown, the mysterious, or even a kiss.

A lot of the thanks for the letter’s seemingly disproportionate presence is due to René Descartes, the 17th-century French philosopher and mathematician. In his groundbreaking Cartesian geometry, he introduced the convention of using x, y, and z in algebra to represent unknowns. More than likely he used these letters simply because they’re the last in the alphabet, and as x is the first of those three, it was used more frequently than the other two.

This system quickly became the standard in Western mathematics, and using x to represent the unknown spread into culture in general. We wouldn’t have The X-Files without Descartes.

Of course we also use X as a general mark, like when we’re voting, or marking where we buried our treasure on a map. I suspect that this came about as an X is a simple, recognisable mark that anyone could make, even if they couldn’t read or write. And in terms of marking a location on a map, the intersection of the two lines in an X allow for a precise spot to be marked.

And I think, even though I said earlier that the letter is alluring despite being the third least-frequently used one in the alphabet, a lot of its appeal is because we don’t get to use it often. Specifically because we don’t usually get to begin words with it. Think of words beginning with all the other letters of the alphabet. Not too hard, is it? Now think of words beginning with X. Not so many, are there?

Calling something Brand X or the XBox therefore gives us a rare opportunity to use this mysterious letter, rendered intriguing simply by how little we get to use it.

One use of X we can be quite sure about though, is why we use X to represent a kiss. In medieval Europe, Christian crosses were used to sign off documents, and people would then place a kiss on these crosses, as a sign of their faith and honesty.

And that’s where that comes from! Cool, eh!? xx