The world without iPhone-style smartphones may seem like a very long time ago. However, it was just sixteen years ago today that Steve Jobs took to the stage at the MacWorld Expo and introduced the device that would change the way we live.

The original iPhone wasn’t the first smartphone, the first MP3 player, or the first mobile internet device. It was, however, the first device to combine these three in a manner that appealed to the general public. And it was primarily its form factor that sold it. By eliminating the physical keyboard and replacing it with a touchscreen, Apple re-invented what we consider a phone in the 21st century.

As Steve Jobs said in his keynote, “the problem is that they’re [smartphones] aren’t so smart, and they’re not so easy to use.” He described the iPhone as a “leapfrog product,” with a “revolutionary UI.” By introducing multitouch capabilities and a version of OS X (later iOS), the iPhone was unlike any other smartphone on the market. Jobs called the user interface “five years ahead of its time,” and allowed it to create “desktop-class applications and networking” for a mobile device.

When the iPhone launched six months later, it quickly became Apple’s most successful product. Thousands of people waited outside Apple stores on launch day to be the first to have one, a tradition that would repeat itself for many years each time Apple released a new model. By the time the original iPhone was discontinued a year later, Apple had sold more than six million units. Just sixteen years later, Apple has sold more than 2.2 billion iPhones.