He wanted to design an attractive interface to convey information in a simple way, for example, an icon to display the weather forecast rather than writing "cloudy".
So Kurita drew a set of images of 12 pixels by 12 pixels that can be selected from a keyboard-like grid in the interface and then sent to cell phones as their own characters. Kurita's 176 emoticons are preferred symbols on faces, as the goal was to find new ways to express information. There were icons to show the weather (sun, clouds, umbrella, snowman), traffic (car, streetcar, plane, boat), technology (landline, cell phone, television).
Emojis and smileys quickly became popular in Japan, as rival mobile companies copied DOCOMO's (NTT DoCoMo) idea. As mobile computing continued to explode in the mid-2000s, companies outside of Japan, such as Apple and Android, had the opportunity to integrate Emoji and smiley faces into the keyboard of their platforms.
In 2007, a team of software developers at Google decided to lead the charge, demanding that emoticons be recognized by the Unicode Consortium a private organization that coordinates the development of the Unicode Standard to maintain text standards across multiple computers. Unicode finally decided to index emoji. This was the beginning of the legitimization of emoji as a form of communication. In other words, emoji and smiley had become too popular to ignore.
The blessing of the Unicode Consortium was not only a way to maintain standards for the existing lexicon, but a standard that will guide the evolution of emojis. Indeed, every year new emoji are proposed and some are selected to be part of the emoji lexicon.
If you want to know even more about emoji, I invite you to read The WIRED Guide to Emoji.
