A few people have asked what I meant in my "boxes" comic. Other just look at me strangely. Some hackers have enjoyed the comic, so I thought I'd try to unpack the meaning of it a bit for the layperson. Of course this will spoil the joke, but what the hey.

A hacker who looks at the comic probably thinks about things like recursion, fractals, unicode, fonts, and bugs.


A font is how the computer knows how to draw the letters on its screen. Before computers, a font was a bunch of metal bits that could be arranged and fed into a printing press. As with most things involving drawing on a screen, font technology is much more complicated these days than you'd ever imagine. Fonts and the programs that draw them (font engines) are something of a mystery even to most hackers.


Unicode is an absurdly complicated version of the alphabet. Or rather, of every alphabet and similar thing used by anyone on earth or in Star Trek. It's not a font, it's a way for the computer to store text internally, by basically assigning a unique number to each letter.

Since most hackers grew up in a world without unicode, and suffered through the (still continuing) transition to it, they're familiar with lots of quirks and weird and broken behaviors you get from it.

One of these quicks is what to do when the computer wants to display a particular letter from unicode, but that letter is not available in the font. Since unicode contains effectively an infinite number of symbols, and each symbol in a font is carefully crafted by hand, this occurs pretty often.

Handling of this situation varies, but often the computer will just display a little empty square box for the letter that it doesn't know how to draw. Some font engines go a step further and write the number of the unicode character in little tiny numbers inside the box. Presumably so that a hacker can look at it and tell what character is missing. The numbers are typically written one in each corner of the box, and you'd have to squint to see them.


A fractal is a special kind of picture, where parts of the picture repeat over and over at different scales. You've probably seen pictures of the most famous fractal, the Maldebrot set. That one is generated by a kind of formula, but there are much simpler ones, like the Koch snowflake.

Hackers love fractals, because they're pretty, and complex, while based on very simple math.


"Recursion: See recursion."

Ha! That's the best hacker joke ever, a true classic. Recursion is when the computer sees an instruction like that and mindlessly repeats it over and over. This actually turns out to be useful, and hackers see a kind of beauty in it.


Bugs are what happens when a computer program, which is supposed to be internally clear and simple, and have well-defined behavior, instead turns out to exhibit unintentional complexity. Kinda like a fractal. This begs the question of whether hackers like bugs, or not. Most of them spend most of their time creating more, so you be the judge.

The bug I'm alluding to in the comic is this: What if the computer, when drawing some word, stumbled over a unicode character that was not in the font. And then say it went to draw the little box instead, and fill in the numbers to indicate what character it was. Except it turned out that its font didn't tell it how to draw the numbers either. And thanks to a really unlikely bug, it then proceeded to recurse, drawing smaller and smaller boxes for these characters that it didn't know how to draw. Until it drew a fractal instead.

See: It's just hilarous once I've explained it.

(And that explanation of the word "cat", by the way, is why I don't try to write most of the technical posts in my blog in a form that a layman could understand.)