In memory of the checkbox

This is a checkbox:

It's square, has a selection mark inside, and its unique feature is that you can select any number of them at the same time:

Different operating systems have rendered them differently throughout their evolution:

As you can see, the check mark wasn't always there. But one thing remained constant: the check boxes were square.

Why square? Because that's how you can identify them by the radio buttons:

Its distinguishing feature is a single choice. If you select one, all the rest will be unchecked.

I'm not sure when the distinction between square/round was introduced, but it seems to have existed as early as the 1990s.

(Guess where) [x]Is it used now? In Markdown! What a comeback, huh?)

And since then, all major operating systems have followed this tradition. In Windows 3.11:

via Windows 95:

for Windows 11:

on Mac OS 4:

up to macOS Sonoma:

There was a brief period of confusion until 1986, when Apple used rounded rectangles instead of circles:

But it was quickly resolved.

The issue is that all major operating system vendors adhere to the convention that checkboxes are square and radio buttons are round.

Then came the Web. And when I say Web, I mean CSS. And when I say CSS, I mean Flash and then JavaScript.

Look, people on the web find conventions boring. They think regular controls need to be reinvented and redesigned. They don't believe there are standards.

That's why it's common to see radio buttons containing check marks:

Or square radio buttons:

Following the example of the web, native applications introduced us to rounded checkboxes:

Sometimes people simply don't make distinctions anymore. For example, here the first group is single choice, while the second is multiple choice:

In other words, one of these surveys is single-answer, and the other is multiple-answer:

How should people know?

But despite all this chaos and temptation, operating system vendors knew this. To this day, they follow the convention: checkboxes are square, radio buttons are round.

Perhaps it was part of their internal training. Perhaps they had experienced art directors. Perhaps it was just luck. I don't know – it doesn't really matter – but – somehow – they managed to follow the convention.

To this day.

Apple is the first major operating system vendor to abandon a four-decade tradition. Its new visionOS – for the first time in Apple's history – will feature round checkboxes.