It's perhaps one of the most important letters in the world — but nobody's entirely sure what it means.
The "i" at the start of iPhone is one of the phone's defining features. And it refers mostly to "internet," though not entirely, and the story of how it got there is slightly more complicated.
The naming convention was introduced with the iMac. Launched in 1998, the computer marked the beginning of the modern Apple.
Introducing that computer, Apple cofounder Steve Jobs said the computer was targeted at the "number one use that the consumers say they want to use the computer for": the internet. It was launched just as the internet was catching on and was made central in the computer's advertising.
"Even though this is a full-blooded Macintosh, we are targeting this for the number one use that consumers tell us they want a computer for, which is to get on the internet — simply, and fast," he said at the time. "And that is what this product is targeted for."
But that was far from the only meaning of the "i," Jobs said. During the launch, he showed a slide with multiple headings: internet, individual, instruct, inform, inspire.
"'I' also means some other things to us," he said. "We are a personal-computer company, and although this product is born to network, it also is a beautiful standalone product. We are targeting it also for education. They want to buy these. And it is perfect for most of the things they do in instruction."
The company would go on to brand almost all of its products with the little letter. Software such as iTools and hardware including the iPod use it. (It still isn't entirely clear where the rest of the iPod name originated.)
It would eventually find its place in the name of the iPhone, a product that had a similar effect for Apple as the iMac.