Anyone with an older Mac probably knows this icon: A boxy all-in-one computer with a simple smiling face on screen.
Like all good symbols, the Happy Mac serves multiple purposes. The official reason it exists is to tell you that your Macintosh has begun the process of booting up without error.
More than that, the Happy Mac was a symbol of intent from Apple: This computer is friendly. It doesn't have an impenetrable interface filled with text you don't understand. The Mac has pictures. And it's smiling at you!
Susan Kare was the graphic designer who created the Happy Mac. She spoke to us about the process behind that and many of the other icons that made the original Macintosh so different to any computer before it.
As the first consumer computer with a graphical interface, the Mac needed to communicate basic concepts with pictures rather than words. But deciding which icon to use isn't as straightforward as it might seem.
For instance, how do you communicate to a user that they need to wait while the computer works on a task? Kare designed a watch icon, reasoning that most people had a wristwatch. And who doesn't glance at their watch impatiently while waiting for something?
But what about a more classical timing device, like an hourglass? Kare told us that a wristwatch could suggest that you only have to wait a matter of seconds, while an hourglass might imply that you could be waiting a much longer time. (Clearly, that reservation wasn't shared by designers at Microsoft: Windows uses an hourglass icon.)
Kare also believes in keeping things as simple as possible. "Just because you have 16 million colors doesn't mean you have to use them all!" She added that extra detail might look nicer, but it could confuse people. "A chrome pen might not look like a writing instrument to everyone, but a pencil does."
And what about Kare's most infamous icon, Clarus the Dogcow? Kare told us it's supposed to be a dog... but it ended up with a more bovine appearance than she intended, leading to confusion over whether it was a dog or a cow.
So, what noise does a dogcow make? That one is easy: Moof!